diff --git a/makefile b/makefile
index 7072404..b0167d4 100644
--- a/makefile
+++ b/makefile
@@ -22,7 +22,7 @@ include common.mk
 CXXFLAGS += `sdl2-config --cflags` -DVERSION=$(VERSION) -DREVISION=$(REVISION) -DDATA_DIR=\"$(DATA_DIR)\" -DLOCALE_DIR=\"$(LOCALE_DIR)\"
 CXXFLAGS += -Wall -Wempty-body -ansi -pedantic -Werror -Wstrict-prototypes -Werror=maybe-uninitialized -Warray-bounds
 CXXFLAGS += -g -lefence
-CXXFLAGS += -fms-extensions
+CXXFLAGS += -fms-extensions -std=gnu11
 
 LDFLAGS += `sdl2-config --libs` -lSDL2_mixer -lSDL2_image -lSDL2_ttf -lm
 
diff --git a/src/combat/combat.c b/src/combat/combat.c
index b19a1c4..6322bb3 100644
--- a/src/combat/combat.c
+++ b/src/combat/combat.c
@@ -32,33 +32,6 @@ void lookForPlayer(void)
 	
 }
 
-void preFire(Entity *e)
-{
-	if (e->flags & EF_WEIGHTLESS)
-	{
-		if (world.bob->y < e->y && e->isOnGround && (int) (rand() % 4) == 0)
-		{
-			e->dy = JUMP_POWER;
-		}
-	}
-
-	e->facing = (world.bob->x < e->x) ? FACING_LEFT : FACING_RIGHT;
-
-	if (e->reload > 0)
-	{
-		return;
-	}
-
-	e->attack();
-
-	e->shotsToFire--;
-
-	if (e->shotsToFire == 0)
-	{
-		e->walk();
-	}
-}
-
 int hasLineOfSight(Entity *src, Entity *dest)
 {
 	return (!isBlockedByMap(src, dest) && !isBlockedByEntities(src, dest));
@@ -130,10 +103,5 @@ static int isBlockedByEntities(Entity *src, Entity *dest)
 
 int enemyCanSeePlayer(Entity *e)
 {
-	return hasLineOfSight(e, world.bob);
-}
-
-int canFire(Entity *target)
-{
-	return 0;
+	return hasLineOfSight(e, (Entity*)world.bob);
 }
diff --git a/src/combat/weapons.c b/src/combat/weapons.c
index 1d1a17a..899222f 100644
--- a/src/combat/weapons.c
+++ b/src/combat/weapons.c
@@ -20,7 +20,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include "weapons.h"
 
-Bullet *createBaseBullet(Entity *owner);
+Bullet *createBaseBullet(Unit *owner);
 
 static int bulletSprite[2];
 static int plasmaSprite[2];
@@ -58,7 +58,7 @@ void initWeapons(void)
 	missileSprite[1] = getSpriteIndex("MissileLeft");
 }
 
-void firePistol(Entity *owner)
+void firePistol(Unit *owner)
 {
 	Bullet *bullet;
 	
@@ -73,7 +73,7 @@ void firePistol(Entity *owner)
 	playSound(SND_PISTOL, CH_PLAYER);
 }
 
-void fireAimedShot(Entity *owner)
+void fireAimedShot(Unit *owner)
 {
 	int x, y;
 	float dx, dy;
@@ -96,7 +96,7 @@ void fireAimedShot(Entity *owner)
 	playSound(SND_PISTOL, CH_WEAPON);
 }
 
-void fireMachineGun(Entity *owner)
+void fireMachineGun(Unit *owner)
 {
 	Bullet *bullet;
 	
@@ -109,7 +109,7 @@ void fireMachineGun(Entity *owner)
 	playSound(SND_MACHINE_GUN, CH_WEAPON);
 }
 
-void firePlasma(Entity *owner)
+void firePlasma(Unit *owner)
 {
 	Bullet *bullet;
 	
@@ -124,7 +124,7 @@ void firePlasma(Entity *owner)
 	playSound(SND_PLASMA, owner->type == ET_BOB ? CH_PLAYER : CH_WEAPON);
 }
 
-void fireSpread(Entity *owner, int numberOfShots)
+void fireSpread(Unit *owner, int numberOfShots)
 {
 	Bullet *bullet;
 	int i;
@@ -148,7 +148,7 @@ void fireSpread(Entity *owner, int numberOfShots)
 	playSound(SND_SPREAD, owner->type == ET_BOB ? CH_PLAYER : CH_WEAPON);
 }
 
-void fireLaser(Entity *owner)
+void fireLaser(Unit *owner)
 {
 	Bullet *laser;
 	
@@ -157,7 +157,6 @@ void fireLaser(Entity *owner)
 	laser->y = owner->y + owner->h / 2;
 	laser->facing = owner->facing;
 	laser->dx = owner->facing == FACING_RIGHT ? 20 : -20;
-	laser->owner = owner;
 	laser->health = FPS * 3;
 	laser->sprite[0] = laser->sprite[1] = (owner->type == ET_BOB) ? laserSprite[0] : laserSprite[1];
 
@@ -166,7 +165,7 @@ void fireLaser(Entity *owner)
 	playSound(SND_LASER, owner->type == ET_BOB ? CH_PLAYER : CH_WEAPON);
 }
 
-void fireGrenade(Entity *owner)
+void fireGrenade(Unit *owner)
 {
 	Bullet *grenade;
 	
@@ -174,7 +173,6 @@ void fireGrenade(Entity *owner)
 	grenade->x = owner->x + owner->w / 2;
 	grenade->y = owner->y;
 	grenade->facing = owner->facing;
-	grenade->owner = owner;
 	grenade->health = FPS * 3;
 	grenade->dx = owner->facing == FACING_RIGHT ? 8 : -8;
 	grenade->sprite[0] = grenade->sprite[1] = (owner->type == ET_BOB) ? grenadeSprite : alienGrenadeSprite;
@@ -186,7 +184,7 @@ void fireGrenade(Entity *owner)
 	playSound(SND_THROW, owner->type == ET_BOB ? CH_PLAYER : CH_WEAPON);
 }
 
-void fireShotgun(Entity *owner)
+void fireShotgun(Unit *owner)
 {
 	int i;
 	float dx, dy;
@@ -211,7 +209,7 @@ void fireShotgun(Entity *owner)
 	playSound(SND_SHOTGUN, CH_WEAPON);
 }
 
-void fireMissile(Entity *owner)
+void fireMissile(Unit *owner)
 {
 	Bullet *missile;
 	
@@ -220,7 +218,6 @@ void fireMissile(Entity *owner)
 	missile->y = owner->y + 10;
 	missile->facing = owner->facing;
 	missile->dx = owner->facing == FACING_RIGHT ? 10 : -10;
-	missile->owner = owner;
 	missile->health = FPS * 3;
 	missile->sprite[0] = missileSprite[0];
 	missile->sprite[1] = missileSprite[1];
@@ -230,21 +227,21 @@ void fireMissile(Entity *owner)
 	playSound(SND_MISSILE, CH_WEAPON);
 }
 
-Bullet *createBaseBullet(Entity *owner)
+Bullet *createBaseBullet(Unit *owner)
 {
 	Bullet *bullet;
 	
 	bullet = malloc(sizeof(Bullet));
 	memset(bullet, 0, sizeof(Bullet));
-	world.bulletTail->next = bullet;
-	world.bulletTail = bullet;
+	world.entityTail->next = (Entity*)bullet;
+	world.entityTail = (Entity*)bullet;
 	
 	bullet->x = (owner->x + owner->w / 2);
 	bullet->y = (owner->y + owner->h / 2) - 3;
 	bullet->dx = owner->facing == FACING_RIGHT ? 15 : -15;
 	bullet->facing = owner->facing;
 	bullet->damage = 1;
-	bullet->owner = owner;
+	bullet->owner = (Entity*)owner;
 	bullet->health = FPS * 3;
 	bullet->flags |= EF_WEIGHTLESS | EF_IGNORE_BULLETS | EF_NO_ENVIRONMENT | EF_KILL_OFFSCREEN | EF_NO_TELEPORT;
 
diff --git a/src/structs.h b/src/structs.h
index 26facce..a7942c3 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -21,7 +21,6 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 typedef struct Texture Texture;
 typedef struct Lookup Lookup;
 typedef struct Quadtree Quadtree;
-typedef struct Entity Entity;
 typedef struct Objective Objective;
 typedef struct Trigger Trigger;
 typedef struct Marker Marker;
@@ -31,7 +30,18 @@ typedef struct Tuple Tuple;
 typedef struct HubMission HubMission;
 typedef struct Widget Widget;
 typedef struct Atlas Atlas;
+
+typedef struct Entity Entity;
+typedef struct EntityExt EntityExt;
+typedef struct Bob Bob;
+typedef struct Boss Boss;
 typedef struct Bullet Bullet;
+typedef struct Decoration Decoration;
+typedef struct Item Item;
+typedef struct MIA MIA;
+typedef struct Structure Structure;
+typedef struct Trap Trap;
+typedef struct Unit Unit;
 
 typedef struct {
 	int debug;
@@ -91,97 +101,131 @@ typedef struct {
 
 struct Entity {
 	unsigned long uniqueId;
-	char name[MAX_NAME_LENGTH];
-	char spriteName[MAX_NAME_LENGTH];
-	char targetNames[MAX_DESCRIPTION_LENGTH];
 	int type;
-	float x;
-	float y;
-	int w;
-	int h;
-	int health;
-	int healthMax;
+	char name[MAX_NAME_LENGTH];
+	float x, y;
+	int w, h;
+	int tx, ty;
+	float dx, dy;
+	int health, healthMax;
 	int alive;
-	int oxygen;
-	int startX;
-	int startY;
-	float dx;
-	float dy;
-	int tx;
-	int ty;
-	int reload;
-	int isOnGround;
-	int effectType;
-	int bleedTime;
+	int active;
+	int environment;
+	int thinkTime;
 	int facing;
-	int damage;
+	int sprite[3];
+	int plane;
+	int isSolid;
+	int isStatic;
+	int isOnGround;
+	int isMissionTarget;
+	SDL_Rect bounds;
+	unsigned long flags;
+	void (*init)(void);
+	void (*action)(void);
+	void (*touch)(Entity *other);
+	void (*tick)(void);
+	void (*reset)(void);
+	void (*die)(void);
+	void (*animate)(void);
+	void (*walk)(void);
+	void (*setSize)(void);
+	float (*bounce)(float x);
+	void (*teleport)(float tx, float ty);
+	void (*activate)(int active);
+	void (*applyDamage)(int amount);
+	void (*changeEnvironment)(void);
+	int (*getCurrentSprite)(void);
+	int (*preSave)(void);
+	SDL_Rect *(*getBounds)(void);
+	Entity *next;
+};
+
+struct EntityExt {
+	struct Entity;
+	char spriteName[MAX_NAME_LENGTH];
+	int spriteTime;
+	int spriteFrame;
+	Item *carriedItem;
+};
+
+struct Unit {
+	struct EntityExt;
 	int weaponType;
+	int canCarryItem;
+	int reload;
 	int shotsToFire;
 	int maxShotsToFire;
-	int isSolid;
-	int environment;
-	int isStatic;
-	int isMissionTarget;
-	int thinkTime;
-	int plane;
-	int value;
-	int canCarryItem;
-	int spawnedIn;
 	int spawnedInTimer;
+	int oxygen;
+	int spawnedIn;
+	int startX, startY;
+	void (*attack)(void);
+	int (*canFire)(Entity *target);
+};
+
+struct MIA {
+	struct Unit;
 	int shudderTimer;
 	int starTimer;
 	int teleportTimer;
-	int stunTimer;
+};
+
+struct Boss {
+	struct Unit;
 	int weakAgainst;
+	int teleportTimer;
+	int stunTimer;
+};
+
+struct Item {
+	struct EntityExt;
+	int startX, startY;
 	int power;
-	int powerMax;
+	int value;
+	int weaponType;
+	int provided;
 	int collected;
 	int canBeCarried;
 	int canBePickedUp;
-	int provided;
-	int firstTouch;
-	int active;
-	float sinVal;
+};
+
+struct Bob {
+	struct Unit;
+	int stunTimer;
+	int power, powerMax;
+};
+
+struct Structure {
+	struct EntityExt;
 	int bobTouching;
-	int messageTimer;
-	char message[MAX_DESCRIPTION_LENGTH];
-	char requiredCard[MAX_NAME_LENGTH];
-	char requiredKey[MAX_NAME_LENGTH];
 	char requiredItem[MAX_NAME_LENGTH];
-	int requiredPower;
-	long flags;
-	SDL_Rect bounds;
-	int sprite[3];
-	int spriteTime;
-	int spriteFrame;
-	int isLocked;
-	int closedX;
-	int closedY;
+	char targetNames[MAX_DESCRIPTION_LENGTH];
+	char message[MAX_DESCRIPTION_LENGTH];
 	int state;
-	int speed;
 	int waitTime;
+	int startX, startY;
+	int closedX, closedY;
+	int isLocked;
+	int speed;
+	int messageTimer;
+	int firstTouch;
+	int requiredPower;
 	int isWeighted;
-	float weightApplied;
+	int weightApplied;
+	float sinVal;
+};
+
+struct Decoration {
+	struct Entity;
+	int effectType;
+	int bleedTime;
+};
+
+struct Trap {
+	struct EntityExt;
 	int onTime;
 	int offTime;
-	Entity *carriedItem;
-	Entity *owner;
-	void (*init)(void);
-	void (*action)(void);
-	void (*walk)(void);
-	void (*attack)(void);
-	void (*touch)(Entity *other);
-	void (*tick)(void);
-	void (*die)(void);
-	int (*canFire)(Entity *target);
-	void (*reset)(void);
-	void (*activate)(int active);
-	void (*changeEnvironment)(void);
-	int (*getCurrentSprite)(void);
-	void (*animate)(void);
-	void (*applyDamage)(int amount);
-	SDL_Rect (*getBounds)(void);
-	Entity *next;
 };
 
 struct Objective {
@@ -357,24 +401,17 @@ struct Particle {
 };
 
 struct Bullet {
-	int x;
-	int y;
-	int facing;
+	struct Entity;
 	int damage;
-	int health;
 	int weaponType;
-	float dx;
-	float dy;
-	int sprite[2];
-	long flags;
 	Entity *owner;
-	Bullet *next;
 };
 
 typedef struct {
 	char id[MAX_NAME_LENGTH];
 	int state;
-	Entity *bob, *boss;
+	Bob *bob;
+	Boss *boss;
 	Map map;
 	int allObjectivesComplete;
 	int frameCounter;
@@ -388,7 +425,6 @@ typedef struct {
 	Quadtree quadtree;
 	Entity entityHead, *entityTail;
 	Particle particleHead, *particleTail;
-	Bullet bulletHead, *bulletTail;
 	Objective objectiveHead, *objectiveTail;
 	Trigger triggerHead, *triggerTail;
 } World;
diff --git a/src/world/effects.c b/src/world/effects.c
index 6056fff..09e778c 100644
--- a/src/world/effects.c
+++ b/src/world/effects.c
@@ -40,12 +40,12 @@ void addExplosionEffect(int x, int y, float dx, float dy)
 
 void addSmallFleshChunk(double x, double y)
 {
-	Entity *chunk;
+	Decoration *chunk;
 	
-	chunk = malloc(sizeof(Entity));
-	memset(chunk, 0, sizeof(Entity));
-	world.entityTail->next = chunk;
-	world.entityTail = chunk;
+	chunk = malloc(sizeof(Decoration));
+	memset(chunk, 0, sizeof(Decoration));
+	world.entityTail->next = (Entity*)chunk;
+	world.entityTail = (Entity*)chunk;
 	
 	chunk->x = x;
 	chunk->y = y;
@@ -58,14 +58,14 @@ void addSmallFleshChunk(double x, double y)
 void throwFleshChunks(double x, double y, int amount)
 {
 	int i;
-	Entity *chunk;
+	Decoration *chunk;
 	
 	for (i = 0; i < amount; i++)
 	{
-		chunk = malloc(sizeof(Entity));
-		memset(chunk, 0, sizeof(Entity));
-		world.entityTail->next = chunk;
-		world.entityTail = chunk;
+		chunk = malloc(sizeof(Decoration));
+		memset(chunk, 0, sizeof(Decoration));
+		world.entityTail->next = (Entity*)chunk;
+		world.entityTail = (Entity*)chunk;
 		
 		chunk->x = x;
 		chunk->y = y;
diff --git a/src/world/entities/blobs/bob.c b/src/world/entities/blobs/bob.c
index e56ae30..633a2b2 100644
--- a/src/world/entities/blobs/bob.c
+++ b/src/world/entities/blobs/bob.c
@@ -20,7 +20,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include "bob.h"
 
-void addBobItem(Entity *e)
+void addBobItem(Item *i)
 {
 	
 }
diff --git a/src/world/entities/blobs/mia.c b/src/world/entities/blobs/mia.c
index 69daf83..77be9b5 100644
--- a/src/world/entities/blobs/mia.c
+++ b/src/world/entities/blobs/mia.c
@@ -28,24 +28,30 @@ static void teleport(void);
 
 void initMIA(Entity *e)
 {
-	e->tx = e->ty = -1;
+	MIA *m;
+	
+	initUnit(e);
+	
+	m = (MIA*)e;
+	
+	m->tx = m->ty = -1;
 
-	e->sprite[FACING_LEFT] = getSpriteIndex("MIA");
-	e->sprite[FACING_RIGHT] = getSpriteIndex("MIA");
-	e->sprite[FACING_DIE] = getSpriteIndex("MIA");
+	m->sprite[FACING_LEFT] = getSpriteIndex("MIA");
+	m->sprite[FACING_RIGHT] = getSpriteIndex("MIA");
+	m->sprite[FACING_DIE] = getSpriteIndex("MIA");
 
-	e->flags |= EF_IGNORE_BULLETS;
+	m->flags |= EF_IGNORE_BULLETS;
 
 	/* blink at random intervals */
-	e->spriteFrame = 0;
-	e->spriteTime = rand() % 180;
+	m->spriteFrame = 0;
+	m->spriteTime = rand() % 180;
 
-	e->action = nothing;
-	e->reset = reset;
-	e->tick = tick;
-	e->touch = touch;
+	m->action = nothing;
+	m->reset = reset;
+	m->tick = tick;
+	m->touch = touch;
 
-	e->isMissionTarget = 1;
+	m->isMissionTarget = 1;
 }
 
 void reinitMIA(Entity *e)
@@ -64,56 +70,72 @@ static void reset(void)
 
 static void tick(void)
 {
-	self->shudderTimer--;
-	if (self->shudderTimer <= 0)
+	MIA *m;
+	
+	m = (MIA*)self;
+	
+	m->shudderTimer--;
+	if (m->shudderTimer <= 0)
 	{
-		self->x = (self->tx + rand() % 4);
-		self->shudderTimer = 2;
+		m->x = (m->tx + rand() % 4);
+		m->shudderTimer = 2;
 	}
 
-	if (self->action != nothing)
+	if (m->action != nothing)
 	{
-		self->starTimer--;
-		if (self->starTimer <= 0)
+		m->starTimer--;
+		if (m->starTimer <= 0)
 		{
-			addMIATeleportStars(self->x + rand() % self->w, self->y + rand() % self->h);
-			self->starTimer = 1;
+			addMIATeleportStars(m->x + rand() % m->w, m->y + rand() % m->h);
+			m->starTimer = 1;
 		}
 	}
 }
 
 static void touch(Entity *other)
 {
-	if (self->action == nothing && other == world.bob)
+	MIA *m;
+	
+	m = (MIA*)self;
+	
+	if (m->action == nothing && other == (Entity*)world.bob)
 	{
-		self->action = preTeleport;
-		self->teleportTimer = FPS * 3;
-		setGameplayMessage(MSG_OBJECTIVE, "Rescued %s", self->name);
-		self->isMissionTarget = 0;
-		self->flags |= EF_ALWAYS_PROCESS;
+		m->action = preTeleport;
+		m->teleportTimer = FPS * 3;
+		setGameplayMessage(MSG_OBJECTIVE, "Rescued %s", m->name);
+		m->isMissionTarget = 0;
+		m->flags |= EF_ALWAYS_PROCESS;
 		playSound(SND_MIA, CH_ANY);
 	}
 }
 
 static void preTeleport(void)
 {
-	self->teleportTimer--;
-	if (self->teleportTimer <= FPS)
+	MIA *m;
+	
+	m = (MIA*)self;
+	
+	m->teleportTimer--;
+	if (m->teleportTimer <= FPS)
 	{
-		self->action = teleport;
-		self->flags |= (EF_NO_CLIP | EF_WEIGHTLESS);
-		self->dy = -5;
+		m->action = teleport;
+		m->flags |= (EF_NO_CLIP | EF_WEIGHTLESS);
+		m->dy = -5;
 	}
 }
 
 static void teleport(void)
 {
-	self->teleportTimer--;
-	if (self->teleportTimer <= 0)
+	MIA *m;
+	
+	m = (MIA*)self;
+	
+	m->teleportTimer--;
+	if (m->teleportTimer <= 0)
 	{
 		addTeleportStars(self);
-		addRescuedMIA(self->name);
+		addRescuedMIA(m->name);
 		updateObjective("MIA");
-		self->alive = ALIVE_DEAD;
+		m->alive = ALIVE_DEAD;
 	}
 }
diff --git a/src/world/entities/blobs/mia.h b/src/world/entities/blobs/mia.h
index 78822d7..0d088c5 100644
--- a/src/world/entities/blobs/mia.h
+++ b/src/world/entities/blobs/mia.h
@@ -28,6 +28,7 @@ extern void setGameplayMessage(int type, char *format, ...);
 extern void playSound(int snd, int ch);
 extern void updateObjective(char *targetName);
 extern void addRescuedMIA(char *name);
+extern void initUnit(Entity *e);
 
 extern Entity *self;
 extern World world;
diff --git a/src/world/entities/blobs/teeka.c b/src/world/entities/blobs/teeka.c
index 5f768e4..d45d7e7 100644
--- a/src/world/entities/blobs/teeka.c
+++ b/src/world/entities/blobs/teeka.c
@@ -31,23 +31,29 @@ static int exitMission;
 
 void initTeeka(Entity *e)
 {
-	e->type = ET_TEEKA;
+	Unit *u;
+	
+	initUnit(e);
+	
+	u = (Unit*)e;
+	
+	u->type = ET_TEEKA;
+	
+	u->flags |= EF_IMMUNE;
 
+	u->action = lookForEnemies;
+
+	u->weaponType = WPN_AIMED_PISTOL;
+
+	u->sprite[FACING_LEFT] = getSpriteIndex("TeekaLeft");
+	u->sprite[FACING_RIGHT] = getSpriteIndex("TeekaRight");
+	u->sprite[FACING_DIE] = getSpriteIndex("TeekaLeft");
+
+	u->health = e->healthMax = 9999;
+	
+	u->tick = tick;
+	
 	aimedSprite = getSpriteIndex("AimedShot");
-	
-	e->flags |= EF_IMMUNE;
-
-	e->action = lookForEnemies;
-
-	e->weaponType = WPN_AIMED_PISTOL;
-
-	e->sprite[FACING_LEFT] = getSpriteIndex("TeekaLeft");
-	e->sprite[FACING_RIGHT] = getSpriteIndex("TeekaRight");
-	e->sprite[FACING_DIE] = getSpriteIndex("TeekaLeft");
-
-	e->health = e->healthMax = 9999;
-	
-	e->tick = tick;
 }
 
 static void tick(void)
@@ -73,8 +79,11 @@ static void lookForEnemies(void)
 {
 	Entity *e;
 	float distance, range;
+	Unit *u;
 	
-	self->thinkTime = rrnd(FPS / 2, FPS);
+	u = (Unit*)self;
+	
+	u->thinkTime = rrnd(FPS / 2, FPS);
 
 	target = NULL;
 	
@@ -84,7 +93,7 @@ static void lookForEnemies(void)
 	{
 		if (e->type == ET_ENEMY)
 		{
-			range = getDistance(self->x, self->y, e->x, e->y);
+			range = getDistance(u->x, u->y, e->x, e->y);
 
 			if (range < distance)
 			{
@@ -99,41 +108,45 @@ static void lookForEnemies(void)
 
 	if (target != NULL)
 	{
-		self->shotsToFire = rrnd(3, 5);
+		u->shotsToFire = rrnd(3, 5);
 
-		self->action = preFire;
+		u->action = preFire;
 	}
 	else if (exitMission)
 	{
 		addTeleportStars(self);
-		self->alive = ALIVE_DEAD;
+		u->alive = ALIVE_DEAD;
 		playSound(SND_APPEAR, CH_ANY);
 	}
 	else
 	{
-		self->facing = rand() % 2 == 0 ? FACING_LEFT : FACING_RIGHT;
+		u->facing = rand() % 2 == 0 ? FACING_LEFT : FACING_RIGHT;
 	}
 }
 
 static void preFire(void)
 {
-	if (self->reload > 0)
+	Unit *u;
+	
+	u = (Unit*)self;
+	
+	if (u->reload > 0)
 	{
 		return;
 	}
 
-	if (target->y < self->y && self->isOnGround && rand() % 10 == 0)
+	if (target->y < u->y && u->isOnGround && rand() % 10 == 0)
 	{
-		self->dy = JUMP_POWER;
+		u->dy = JUMP_POWER;
 	}
 
 	attack();
 
-	self->shotsToFire--;
+	u->shotsToFire--;
 
-	if (self->shotsToFire == 0)
+	if (u->shotsToFire == 0)
 	{
-		self->thinkTime = FPS;
+		u->thinkTime = FPS;
 	}
 }
 
@@ -144,7 +157,7 @@ static void attack(void)
 	
 	getSlope(target->x, target->y, self->x, self->y, &dx, &dy);
 
-	bullet = createBaseBullet(self);
+	bullet = createBaseBullet((Unit*)self);
 	bullet->x = self->x;
 	bullet->y = (self->y + self->h / 2) - 3;
 	bullet->facing = self->facing;
@@ -157,7 +170,7 @@ static void attack(void)
 	bullet->sprite[0] = bullet->sprite[1] = aimedSprite;
 	bullet->health *= 2;
 
-	self->reload = 5;
+	((Unit*)self)->reload = 5;
 }
 
 void teekaExitMission(void)
diff --git a/src/world/entities/blobs/teeka.h b/src/world/entities/blobs/teeka.h
index b501ed5..3b178ea 100644
--- a/src/world/entities/blobs/teeka.h
+++ b/src/world/entities/blobs/teeka.h
@@ -20,10 +20,11 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include "../../../common.h"
 
+extern void initUnit(Entity *e);
 extern void unitTick(void);
 extern int getSpriteIndex(char *name);
 extern int rrnd(int low, int high);
-extern Bullet *createBaseBullet(Entity *owner);
+extern Bullet *createBaseBullet(Unit *owner);
 extern void getSlope(int x1, int y1, int x2, int y2, float *dx, float *dy);
 extern int getDistance(int x1, int y1, int x2, int y2);
 extern int hasLineOfSight(Entity *src, Entity *dest);
diff --git a/src/world/entities/boss/blaze.c b/src/world/entities/boss/blaze.c
index 941a8a8..e2155b8 100644
--- a/src/world/entities/boss/blaze.c
+++ b/src/world/entities/boss/blaze.c
@@ -22,13 +22,17 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 void initBlaze(Entity *e)
 {
-	initBlobBoss(e);
+	Boss *b;
 	
-	e->weakAgainst = ENV_WATER;
+	b = (Boss*)e;
 	
-	STRNCPY(e->name, "Blaze", MAX_NAME_LENGTH);
+	initBlobBoss(b);
+	
+	b->weakAgainst = ENV_WATER;
+	
+	STRNCPY(b->name, "Blaze", MAX_NAME_LENGTH);
 
-	e->sprite[FACING_LEFT] = getSpriteIndex("BlazeLeft");
-	e->sprite[FACING_RIGHT] = getSpriteIndex("BlazeRight");
-	e->sprite[FACING_DIE] = getSpriteIndex("BlazeSpin");
+	b->sprite[FACING_LEFT] = getSpriteIndex("BlazeLeft");
+	b->sprite[FACING_RIGHT] = getSpriteIndex("BlazeRight");
+	b->sprite[FACING_DIE] = getSpriteIndex("BlazeSpin");
 }
diff --git a/src/world/entities/boss/blaze.h b/src/world/entities/boss/blaze.h
index 54f352c..dbbb9f5 100644
--- a/src/world/entities/boss/blaze.h
+++ b/src/world/entities/boss/blaze.h
@@ -20,5 +20,5 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include "../../../common.h"
 
-extern void initBlobBoss(Entity *e);
+extern void initBlobBoss(Boss *b);
 extern int getSpriteIndex(char *name);
diff --git a/src/world/entities/boss/blobBoss.c b/src/world/entities/boss/blobBoss.c
index 88eb0d6..f488de8 100644
--- a/src/world/entities/boss/blobBoss.c
+++ b/src/world/entities/boss/blobBoss.c
@@ -38,24 +38,28 @@ static int aimedSprite;
 
 void initBlobBoss(Entity *e)
 {
+	Boss *b;
+	
 	initBoss(e);
 	
+	b = (Boss*)e;
+	
+	b->flags |= EF_HALT_AT_EDGE;
+
+	b->health = b->healthMax = 250;
+
+	b->teleportTimer = FPS * rrnd(4, 6);
+	
+	b->activate = activate;
+	b->walk = walk;
+	b->tick = tick;
+	b->changeEnvironment = changeEnvironment;
+	b->getCurrentSprite = getCurrentSprite;
+	b->animate = animate;
+	b->applyDamage = applyDamage;
+	b->die = die1;
+	
 	aimedSprite = getSpriteIndex("AimedShot");
-	
-	e->flags |= EF_HALT_AT_EDGE;
-
-	e->health = e->healthMax = 250;
-
-	e->teleportTimer = FPS * rrnd(4, 6);
-	
-	e->activate = activate;
-	e->walk = walk;
-	e->tick = tick;
-	e->changeEnvironment = changeEnvironment;
-	e->getCurrentSprite = getCurrentSprite;
-	e->animate = animate;
-	e->applyDamage = applyDamage;
-	e->die = die1;
 }
 
 static void activate(int activate)
@@ -74,32 +78,36 @@ static void activate(int activate)
 
 static void tick(void)
 {
-	if (self->health > 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->health > 0)
 	{
-		self->stunTimer = MAX(self->stunTimer - 1, 0);
+		b->stunTimer = MAX(b->stunTimer - 1, 0);
 
-		if (self->environment == self->weakAgainst)
+		if (b->environment == b->weakAgainst)
 		{
-			self->health -= 2;
+			b->health -= 2;
 
-			world.boss = self;
+			world.boss = b;
 		}
 
-		if (self->stunTimer == 0)
+		if (b->stunTimer == 0)
 		{
-			self->facing = (world.bob->x < self->x) ? FACING_LEFT : FACING_RIGHT;
+			b->facing = (world.bob->x < b->x) ? FACING_LEFT : FACING_RIGHT;
 
-			self->reload = limit(--self->reload, 0, FPS);
+			b->reload = limit(--b->reload, 0, FPS);
 
-			self->teleportTimer = limit(self->teleportTimer - 1, 0, 9999);
+			b->teleportTimer = limit(b->teleportTimer - 1, 0, 9999);
 
-			if (self->isOnGround)
+			if (b->isOnGround)
 			{
-				self->flags |= EF_HALT_AT_EDGE;
+				b->flags |= EF_HALT_AT_EDGE;
 			}
 			else
 			{
-				self->flags &= ~EF_HALT_AT_EDGE;
+				b->flags &= ~EF_HALT_AT_EDGE;
 			}
 		}
 	}
@@ -107,35 +115,43 @@ static void tick(void)
 
 static void changeEnvironment()
 {
-	if (self->environment == self->weakAgainst)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->environment == b->weakAgainst)
 	{
-		self->teleportTimer = 0;
-		self->stunTimer = 90;
-		self->spriteFrame = self->spriteTime = 0;
+		b->teleportTimer = 0;
+		b->stunTimer = 90;
+		b->spriteFrame = b->spriteTime = 0;
 	}
 	else
 	{
-		self->teleportTimer = 0;
+		b->teleportTimer = 0;
 	}
 }
 
 static void die1(void)
 {
-	self->flags |= EF_BOUNCES;
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->flags |= EF_BOUNCES;
 
-	self->thinkTime = 0;
+	b->thinkTime = 0;
 
-	self->spriteTime = 0;
-	self->spriteFrame = 0;
+	b->spriteTime = 0;
+	b->spriteFrame = 0;
 
-	if (self->environment == ENV_AIR)
+	if (b->environment == ENV_AIR)
 	{
-		self->dy = -9;
+		b->dy = -9;
 	}
 
-	self->dx = (randF() - randF()) * 5;
+	b->dx = (randF() - randF()) * 5;
 
-	self->flags &= ~EF_HALT_AT_EDGE;
+	b->flags &= ~EF_HALT_AT_EDGE;
 
 	switch (rand() % 3)
 	{
@@ -152,22 +168,30 @@ static void die1(void)
 			break;
 	}
 	
-	self->action = die2;
+	b->action = die2;
 }
 
 static int getCurrentSprite(void)
 {
-	if (self->stunTimer > 0 || self->health <= 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->stunTimer > 0 || b->health <= 0)
 	{
-		return self->sprite[FACING_DIE];
+		return b->sprite[FACING_DIE];
 	}
 
-	return self->sprite[self->facing];
+	return b->sprite[b->facing];
 }
 
 static void animate(void)
 {
-	if (self->dx != 0 || self->health <= 0 || self->stunTimer > 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->dx != 0 || b->health <= 0 || b->stunTimer > 0)
 	{
 		animateEntity(self);
 	}
@@ -175,9 +199,13 @@ static void animate(void)
 
 static void lookForPlayer(void)
 {
-	self->thinkTime = rrnd(0, FPS / 2);
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->thinkTime = rrnd(0, FPS / 2);
 
-	if (getDistance(world.bob->x, world.bob->y, self->x, self->y) > 650)
+	if (getDistance(world.bob->x, world.bob->y, b->x, b->y) > 650)
 	{
 		moveTowardsPlayer();
 		return;
@@ -191,8 +219,8 @@ static void lookForPlayer(void)
 
 	if (rand() % 100 < 15)
 	{
-		self->shotsToFire = rrnd(1, 12);
-		self->action = preFire;
+		b->shotsToFire = rrnd(1, 12);
+		b->action = preFire;
 	}
 
 	moveTowardsPlayer();
@@ -200,48 +228,56 @@ static void lookForPlayer(void)
 
 static void moveTowardsPlayer(void)
 {
-	self->dx = 0;
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->dx = 0;
 
 	if (rand() % 100 < 20)
 	{
-		if (world.bob->x < self->x)
+		if (world.bob->x < b->x)
 		{
-			self->dx = -3.5;
+			b->dx = -3.5;
 		}
 
-		if (world.bob->x > self->x)
+		if (world.bob->x > b->x)
 		{
-			self->dx = 3.5;
+			b->dx = 3.5;
 		}
 
-		if (world.bob->y <= self->y && rand() % 2 == 0 && self->isOnGround)
+		if (world.bob->y <= b->y && rand() % 2 == 0 && b->isOnGround)
 		{
-			self->dy = JUMP_POWER;
+			b->dy = JUMP_POWER;
 		}
 	}
 
-	if (self->stunTimer == 0 && self->teleportTimer == 0)
+	if (b->stunTimer == 0 && b->teleportTimer == 0)
 	{
 		teleport();
 
-		self->teleportTimer = FPS * rrnd(4, 6);
+		b->teleportTimer = FPS * rrnd(4, 6);
 	}
 }
 
 static void preFire(void)
 {
-	if (self->reload > 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->reload > 0)
 	{
 		return;
 	}
 
 	attack();
 
-	self->shotsToFire--;
+	b->shotsToFire--;
 
-	if (self->shotsToFire == 0)
+	if (b->shotsToFire == 0)
 	{
-		self->walk();
+		b->walk();
 	}
 }
 
@@ -256,7 +292,7 @@ static void attack(void)
 
 	getSlope(bx, by, self->x, self->y, &dx, &dy);
 
-	bullet = createBaseBullet(self);
+	bullet = createBaseBullet((Unit*)self);
 	bullet->x = self->x;
 	bullet->y = (self->y + self->h / 2) - 3;
 	bullet->facing = self->facing;
@@ -268,7 +304,7 @@ static void attack(void)
 	bullet->dy = dy * 12;
 	bullet->sprite[0] = bullet->sprite[1] = aimedSprite;
 
-	self->reload = 4;
+	((Boss*)self)->reload = 4;
 
 	playSound(SND_MACHINE_GUN, CH_WEAPON);
 }
@@ -315,7 +351,7 @@ static void applyDamage(int amount)
 		teleport();
 	}
 
-	world.boss = self;
+	world.boss = (Boss*)self;
 }
 
 static void teleport(void)
@@ -329,19 +365,23 @@ static void teleport(void)
 
 static void die2(void)
 {
-	self->health--;
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->health--;
 
-	if (self->health <= -FPS)
+	if (b->health <= -FPS)
 	{
 		addTeleportStars(self);
 
 		playSound(SND_APPEAR, CH_ANY);
 
-		self->alive = ALIVE_DEAD;
+		b->alive = ALIVE_DEAD;
 
-		updateObjective(self->name);
+		updateObjective(b->name);
 
-		addDefeatedTarget(self->name);
+		addDefeatedTarget(b->name);
 
 		game.enemiesKilled++;
 	}
diff --git a/src/world/entities/boss/blobBoss.h b/src/world/entities/boss/blobBoss.h
index df15c2b..314d825 100644
--- a/src/world/entities/boss/blobBoss.h
+++ b/src/world/entities/boss/blobBoss.h
@@ -29,7 +29,7 @@ extern float limit(float i, float a, float b);
 extern double randF(void);
 extern void playSound(int snd, int ch);
 extern void animateEntity(Entity *e);
-extern Bullet *createBaseBullet(Entity *owner);
+extern Bullet *createBaseBullet(Unit *owner);
 extern int getSpriteIndex(char *name);
 extern int getDistance(int x1, int y1, int x2, int y2);
 extern void getSlope(int x1, int y1, int x2, int y2, float *dx, float *dy);
diff --git a/src/world/entities/boss/boss.c b/src/world/entities/boss/boss.c
index 544beae..8df2d28 100644
--- a/src/world/entities/boss/boss.c
+++ b/src/world/entities/boss/boss.c
@@ -22,18 +22,22 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 void initBoss(Entity *e)
 {
+	Boss *b;
+	
 	initEntity(e);
 	
-	e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex("Boss");
+	b = (Boss*)e;
 	
-	e->isMissionTarget = 1;
+	b->sprite[FACING_LEFT] = b->sprite[FACING_RIGHT] = b->sprite[FACING_DIE] = getSpriteIndex("Boss");
+	
+	b->isMissionTarget = 1;
 
-	e->action = lookForPlayer;
+	b->action = lookForPlayer;
 
-	e->spriteFrame = 0;
-	e->spriteTime = 0;
+	b->spriteFrame = 0;
+	b->spriteTime = 0;
 
-	world.boss = e;
+	world.boss = b;
 
-	e->flags |= EF_ALWAYS_PROCESS | EF_BOMB_SHIELD | EF_GONE;
+	b->flags |= EF_ALWAYS_PROCESS | EF_BOMB_SHIELD | EF_GONE;
 }
diff --git a/src/world/entities/boss/eyeDroidCommander.c b/src/world/entities/boss/eyeDroidCommander.c
index 2a2ff1b..be38a0c 100644
--- a/src/world/entities/boss/eyeDroidCommander.c
+++ b/src/world/entities/boss/eyeDroidCommander.c
@@ -42,23 +42,27 @@ static int plasmaSprite[2];
 
 void initEyeDroidCommander(Entity *e)
 {
+	Boss *b;
+	
 	initBoss(e);
 	
-	STRNCPY(e->name, "EyeDroid Commander", MAX_NAME_LENGTH);
-
-	e->sprite[FACING_LEFT] = getSpriteIndex("DroidCommanderLeft");
-	e->sprite[FACING_RIGHT] = getSpriteIndex("DroidCommanderRight");
-	e->sprite[FACING_DIE] = getSpriteIndex("DroidCommanderDie");
+	b = (Boss*)e;
 	
-	e->flags |= EF_WEIGHTLESS | EF_EXPLODES;
+	STRNCPY(b->name, "EyeDroid Commander", MAX_NAME_LENGTH);
 
-	e->health = e->healthMax = 250;
+	b->sprite[FACING_LEFT] = getSpriteIndex("DroidCommanderLeft");
+	b->sprite[FACING_RIGHT] = getSpriteIndex("DroidCommanderRight");
+	b->sprite[FACING_DIE] = getSpriteIndex("DroidCommanderDie");
 	
-	e->walk = walk;
-	e->tick = tick;
-	e->activate = activate;
-	e->applyDamage = applyDamage;
-	e->getCurrentSprite = getCurrentSprite;
+	b->flags |= EF_WEIGHTLESS | EF_EXPLODES;
+
+	b->health = b->healthMax = 250;
+	
+	b->walk = walk;
+	b->tick = tick;
+	b->activate = activate;
+	b->applyDamage = applyDamage;
+	b->getCurrentSprite = getCurrentSprite;
 
 	brakingTimer = 0;
 	
@@ -84,23 +88,27 @@ static void activate(int activate)
 
 static void tick(void)
 {
-	if (self->health > 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->health > 0)
 	{
-		self->facing = (world.bob->x < self->x) ? FACING_LEFT : FACING_RIGHT;
+		b->facing = (world.bob->x < b->x) ? FACING_LEFT : FACING_RIGHT;
 
-		self->reload = (int) limit(self->reload - 1, 0, FPS);
+		b->reload = (int) limit(b->reload - 1, 0, FPS);
 
 		brakingTimer = (int) limit(--brakingTimer, 0, FPS);
 
 		if (brakingTimer > 0)
 		{
-			self->dx *= 0.95;
-			self->dy *= 0.95;
+			b->dx *= 0.95;
+			b->dy *= 0.95;
 		}
 	}
 	else
 	{
-		addSmokeParticles(self->x + (self->w / 2), self->y);
+		addSmokeParticles(b->x + (b->w / 2), b->y);
 	}
 }
 
@@ -135,23 +143,27 @@ static void lookForPlayer(void)
 
 static void selectWeapon(void)
 {
+	Boss *b;
+	
+	b = (Boss*)self;
+	
 	if (world.bob->isOnGround || abs(self->y - world.bob->y) > 64)
 	{
-		self->weaponType = WPN_AIMED_PISTOL;
-		self->shotsToFire = rrnd(1, 12);
-		self->action = preFire;
+		b->weaponType = WPN_AIMED_PISTOL;
+		b->shotsToFire = rrnd(1, 12);
+		b->action = preFire;
 	}
 	else if (rand() % 4 == 0)
 	{
-		self->weaponType = WPN_MISSILE;
-		self->shotsToFire = rrnd(1, 3);
-		self->action = preFire;
+		b->weaponType = WPN_MISSILE;
+		b->shotsToFire = rrnd(1, 3);
+		b->action = preFire;
 	}
 	else
 	{
-		self->weaponType = WPN_PLASMA;
-		self->shotsToFire = rrnd(1, 12);
-		self->action = preFire;
+		b->weaponType = WPN_PLASMA;
+		b->shotsToFire = rrnd(1, 12);
+		b->action = preFire;
 	}
 }
 
@@ -191,24 +203,32 @@ static void moveTowardsPlayer(void)
 
 static void preFire(void)
 {
-	if (self->reload > 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->reload > 0)
 	{
 		return;
 	}
 
 	attack();
 
-	self->shotsToFire--;
+	b->shotsToFire--;
 
-	if (self->shotsToFire == 0)
+	if (b->shotsToFire == 0)
 	{
-		self->walk();
+		b->walk();
 	}
 }
 
 static void attack(void)
 {
-	switch (self->weaponType)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	switch (b->weaponType)
 	{
 		case WPN_AIMED_PISTOL:
 			attackPistol();
@@ -229,13 +249,16 @@ static void attackPistol(void)
 	int bx, by;
 	float dx, dy;
 	Bullet *bullet;
+	Boss *b;
+	
+	b = (Boss*)self;
 	
 	bx = world.bob->x + rrnd(-8, 24);
 	by = world.bob->y + rrnd(-8, 24);
 
 	getSlope(bx, by, self->x, self->y, &dx, &dy);
 
-	bullet = createBaseBullet(self);
+	bullet = createBaseBullet((Unit*)self);
 	bullet->x = (self->x + self->w / 2);
 	bullet->y = (self->y + self->h / 2) - 3;
 	bullet->facing = self->facing;
@@ -247,16 +270,19 @@ static void attackPistol(void)
 	bullet->dy = dy * 12;
 	bullet->sprite[0] = bullet->sprite[1] = aimedSprite;
 
-	self->reload = 4;
+	b->reload = 4;
 
 	playSound(SND_MACHINE_GUN, CH_WEAPON);
 }
 
 static void attackPlasma(void)
 {
+	Boss *b;
 	Bullet *bullet;
 	
-	bullet = createBaseBullet(self);
+	b = (Boss*)self;
+	
+	bullet = createBaseBullet((Unit*)self);
 	bullet->x = (self->x + self->w / 2);
 	bullet->y = (self->y + self->h / 2) - 3;
 	bullet->facing = self->facing;
@@ -269,26 +295,29 @@ static void attackPlasma(void)
 	bullet->sprite[0] = plasmaSprite[0];
 	bullet->sprite[1] = plasmaSprite[1];
 
-	self->reload = 4;
+	b->reload = 4;
 
 	playSound(SND_PLASMA, CH_WEAPON);
 }
 
 static void attackMissile(void)
 {
+	Boss *b;
 	Bullet *missile;
 	
-	missile = createBaseBullet(self);
-	missile->x = self->x + self->w / 2;
-	missile->y = self->y + self->h / 2;
-	missile->facing = self->facing;
-	missile->dx = self->facing == FACING_RIGHT ? 15 : -15;
+	b = (Boss*)self;
+	
+	missile = createBaseBullet((Unit*)self);
+	missile->x = b->x + b->w / 2;
+	missile->y = b->y + b->h / 2;
+	missile->facing = b->facing;
+	missile->dx = b->facing == FACING_RIGHT ? 15 : -15;
 	missile->owner = self;
 	missile->health = FPS * 3;
 	missile->sprite[0] = missileSprite[0];
 	missile->sprite[1] = missileSprite[1];
 
-	self->reload = 15;
+	b->reload = 15;
 
 	playSound(SND_MISSILE, CH_WEAPON);
 }
@@ -306,16 +335,20 @@ static void applyDamage(int amount)
 
 static void die1(void)
 {
-	self->dx = (randF() - randF()) * 3;
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->dx = (randF() - randF()) * 3;
 
-	self->spriteTime = 0;
-	self->spriteFrame = 0;
+	b->spriteTime = 0;
+	b->spriteFrame = 0;
 
-	self->action = die2;
-	self->thinkTime = 0;
-	self->flags &= ~(EF_WEIGHTLESS | EF_HALT_AT_EDGE);
+	b->action = die2;
+	b->thinkTime = 0;
+	b->flags &= ~(EF_WEIGHTLESS | EF_HALT_AT_EDGE);
 
-	self->dy = JUMP_POWER;
+	b->dy = JUMP_POWER;
 
 	if (rand() % 2)
 	{
@@ -329,17 +362,21 @@ static void die1(void)
 
 static void die2()
 {
-	if (self->isOnGround)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->isOnGround)
 	{
 		addTeleportStars(self);
 
 		playSound(SND_APPEAR, CH_ANY);
 
-		self->alive = ALIVE_DEAD;
+		b->alive = ALIVE_DEAD;
 
-		updateObjective(self->name);
+		updateObjective(b->name);
 
-		addDefeatedTarget(self->name);
+		addDefeatedTarget(b->name);
 
 		game.enemiesKilled++;
 	}
diff --git a/src/world/entities/boss/eyeDroidCommander.h b/src/world/entities/boss/eyeDroidCommander.h
index 91acc5a..c272917 100644
--- a/src/world/entities/boss/eyeDroidCommander.h
+++ b/src/world/entities/boss/eyeDroidCommander.h
@@ -33,7 +33,7 @@ extern void addDefeatedTarget(char *name);
 extern void updateObjective(char *targetName);
 extern double randF(void);
 extern void playSound(int snd, int ch);
-extern Bullet *createBaseBullet(Entity *owner);
+extern Bullet *createBaseBullet(Unit *owner);
 extern void getSlope(int x1, int y1, int x2, int y2, float *dx, float *dy);
 extern void addExplosion(float x, float y, int radius, Entity *owner);
 
diff --git a/src/world/entities/boss/frost.c b/src/world/entities/boss/frost.c
index a674882..93aefe4 100644
--- a/src/world/entities/boss/frost.c
+++ b/src/world/entities/boss/frost.c
@@ -22,13 +22,17 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 void initFrost(Entity *e)
 {
+	Boss *b;
+	
 	initBlobBoss(e);
 	
-	e->weakAgainst = ENV_LAVA;
+	b = (Boss*)e;
 	
-	STRNCPY(e->name, "Frost", MAX_NAME_LENGTH);
+	b->weakAgainst = ENV_LAVA;
+	
+	STRNCPY(b->name, "Frost", MAX_NAME_LENGTH);
 
-	e->sprite[FACING_LEFT] = getSpriteIndex("FrostLeft");
-	e->sprite[FACING_RIGHT] = getSpriteIndex("FrostRight");
-	e->sprite[FACING_DIE] = getSpriteIndex("FrostSpin");
+	b->sprite[FACING_LEFT] = getSpriteIndex("FrostLeft");
+	b->sprite[FACING_RIGHT] = getSpriteIndex("FrostRight");
+	b->sprite[FACING_DIE] = getSpriteIndex("FrostSpin");
 }
diff --git a/src/world/entities/boss/tankCommander.c b/src/world/entities/boss/tankCommander.c
index 9e3bcf9..d178ecf 100644
--- a/src/world/entities/boss/tankCommander.c
+++ b/src/world/entities/boss/tankCommander.c
@@ -29,7 +29,7 @@ static void die1(void);
 static void die2(void);
 static void attack(void);
 static void applyDamage(int amount);
-static SDL_Rect getBounds(void);
+static SDL_Rect *getBounds(void);
 static void preFire(void);
 static void selectWeapon(void);
 static void moveTowardsPlayer(void);
@@ -41,28 +41,32 @@ static int aimedSprite;
 
 void initTankCommander(Entity *e)
 {
+	Boss *b;
+	
 	initBoss(e);
+	
+	b = (Boss*)e;
 
 	STRNCPY(e->name, "Tank Commander", MAX_NAME_LENGTH);
 
-	e->sprite[FACING_LEFT] = getSpriteIndex("TankCommanderLeft");
-	e->sprite[FACING_RIGHT] = getSpriteIndex("TankCommanderRight");
-	e->sprite[FACING_DIE] = getSpriteIndex("TankCommanderDie");
+	b->sprite[FACING_LEFT] = getSpriteIndex("TankCommanderLeft");
+	b->sprite[FACING_RIGHT] = getSpriteIndex("TankCommanderRight");
+	b->sprite[FACING_DIE] = getSpriteIndex("TankCommanderDie");
 
-	e->flags |= EF_EXPLODES;
+	b->flags |= EF_EXPLODES;
 
-	e->health = e->healthMax = 400;
+	b->health = e->healthMax = 400;
 
-	e->activate = activate;
-	e->walk = walk;
-	e->tick = tick;
-	e->die = die1;
-	e->applyDamage = applyDamage;
-	e->getBounds = getBounds;
+	b->activate = activate;
+	b->walk = walk;
+	b->tick = tick;
+	b->die = die1;
+	b->applyDamage = applyDamage;
+	b->getBounds = getBounds;
 
 	brakingTimer = 0;
 
-	world.boss = e;
+	world.boss = b;
 	
 	aimedSprite = getSpriteIndex("AimedShot");
 
@@ -74,7 +78,11 @@ void initTankCommander(Entity *e)
 
 static void activate(int activate)
 {
-	self->flags &= ~EF_GONE;
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->flags &= ~EF_GONE;
 	tankTrack->flags &= ~EF_GONE;
 
 	world.isBossActive = 1;
@@ -87,32 +95,40 @@ static void activate(int activate)
 
 static void tick(void)
 {
-	if (self->health > 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->health > 0)
 	{
-		self->facing = (world.bob->x < self->x) ? FACING_LEFT : FACING_RIGHT;
+		b->facing = (world.bob->x < b->x) ? FACING_LEFT : FACING_RIGHT;
 
-		self->reload = limit(self->reload - 1, 0, FPS);
+		b->reload = limit(b->reload - 1, 0, FPS);
 
 		brakingTimer = limit(brakingTimer - 1, 0, FPS);
 
 		if (brakingTimer > 0)
 		{
-			self->dx *= 0.9;
-			self->dy *= 0.9;
+			b->dx *= 0.9;
+			b->dy *= 0.9;
 		}
 	}
 }
 
 static void lookForPlayer(void)
 {
-	self->thinkTime = rrnd(0, FPS / 2);
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->thinkTime = rrnd(0, FPS / 2);
 
 	if (rand() % 10 == 0)
 	{
 		brakingTimer = rrnd(60, 120);
 	}
 
-	if (getDistance(world.bob->x, world.bob->y, self->x, self->y) > 650)
+	if (getDistance(world.bob->x, world.bob->y, b->x, b->y) > 650)
 	{
 		moveTowardsPlayer();
 		return;
@@ -157,23 +173,31 @@ static void moveTowardsPlayer(void)
 
 static void selectWeapon(void)
 {
-	if (abs(self->y - world.bob->y) > 64)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (abs(b->y - world.bob->y) > 64)
 	{
-		self->weaponType = WPN_AIMED_PISTOL;
-		self->shotsToFire = rrnd(4, 12);
-		self->action = preFire;
+		b->weaponType = WPN_AIMED_PISTOL;
+		b->shotsToFire = rrnd(4, 12);
+		b->action = preFire;
 	}
 	else
 	{
-		self->weaponType = WPN_MISSILE;
-		self->shotsToFire = rrnd(1, 3);
-		self->action = preFire;
+		b->weaponType = WPN_MISSILE;
+		b->shotsToFire = rrnd(1, 3);
+		b->action = preFire;
 	}
 }
 
 static void preFire(void)
 {
-	if (self->reload > 0)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	if (b->reload > 0)
 	{
 		moveTowardsPlayer();
 		return;
@@ -181,17 +205,21 @@ static void preFire(void)
 
 	attack();
 
-	self->shotsToFire--;
+	b->shotsToFire--;
 
-	if (self->shotsToFire == 0)
+	if (b->shotsToFire == 0)
 	{
-		self->walk();
+		b->walk();
 	}
 }
 
 static void attack(void)
 {
-	switch (self->weaponType)
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	switch (b->weaponType)
 	{
 		case WPN_AIMED_PISTOL:
 			attackPistol();
@@ -209,16 +237,19 @@ static void attackPistol(void)
 	int bx, by;
 	float dx, dy;
 	Bullet *bullet;
+	Boss *b;
+	
+	b = (Boss*)self;
 	
 	bx = world.bob->x + rrnd(-8, 24);
 	by = world.bob->y + rrnd(-8, 24);
 
-	getSlope(bx, by, self->x, self->y, &dx, &dy);
+	getSlope(bx, by, b->x, b->y, &dx, &dy);
 
-	bullet = createBaseBullet(self);
-	bullet->x = (self->x + self->w / 2);
-	bullet->y = self->y + 30;
-	bullet->facing = self->facing;
+	bullet = createBaseBullet((Unit*)self);
+	bullet->x = (b->x + b->w / 2);
+	bullet->y = b->y + 30;
+	bullet->facing = b->facing;
 	bullet->damage = 1;
 	bullet->owner = self;
 	bullet->health = FPS * 3;
@@ -227,7 +258,7 @@ static void attackPistol(void)
 	bullet->dy = dy * 12;
 	bullet->sprite[0] = bullet->sprite[1] = aimedSprite;
 
-	self->reload = 4;
+	b->reload = 4;
 
 	playSound(SND_MACHINE_GUN, CH_WEAPON);
 }
@@ -235,12 +266,15 @@ static void attackPistol(void)
 static void attackMissile(void)
 {
 	Bullet *missile;
+	Boss *b;
+	
+	b = (Boss*)self;
 
-	missile = createBaseBullet(self);
-	missile->x = self->x + self->w / 2;
-	missile->y = self->y + 30;
-	missile->facing = self->facing;
-	missile->dx = self->facing == FACING_RIGHT ? 15 : -15;
+	missile = createBaseBullet((Unit*)self);
+	missile->x = b->x + b->w / 2;
+	missile->y = b->y + 30;
+	missile->facing = b->facing;
+	missile->dx = b->facing == FACING_RIGHT ? 15 : -15;
 	missile->dy = world.bob->y - missile->y;
 	missile->dy *= 0.01;
 	missile->owner = self;
@@ -248,50 +282,57 @@ static void attackMissile(void)
 	missile->sprite[0] = missileSprite[0];
 	missile->sprite[1] = missileSprite[1];
 
-	self->reload = 15;
+	b->reload = 15;
 
 	playSound(SND_MISSILE, CH_WEAPON);
 }
 
 static void die1(void)
 {
-	self->flags |= EF_BOUNCES;
+	Boss *b;
+	
+	b = (Boss*)self;
+	
+	b->flags |= EF_BOUNCES;
 
-	self->action = die2;
-	self->thinkTime = 0;
+	b->action = die2;
+	b->thinkTime = 0;
 
-	self->spriteTime = 0;
-	self->spriteFrame = 0;
+	b->spriteTime = 0;
+	b->spriteFrame = 0;
 }
 
 static void die2(void)
 {
 	int mx, my;
+	Boss *b;
+	
+	b = (Boss*)self;
 
-	self->health--;
+	b->health--;
 
-	if (self->health % 3 == 0)
+	if (b->health % 3 == 0)
 	{
-		mx = (int) ((self->x + (self->w / 2)) / MAP_TILE_SIZE);
-		my = (int) ((self->y + self->h) / MAP_TILE_SIZE);
+		mx = (int) ((b->x + (b->w / 2)) / MAP_TILE_SIZE);
+		my = (int) ((b->y + b->h) / MAP_TILE_SIZE);
 		
 		addScorchDecal(mx, my);
 
-		addExplosion(self->x + rand() % self->w, self->y + rand() % self->h, 50, self);
+		addExplosion(b->x + rand() % b->w, b->y + rand() % b->h, 50, self);
 	}
 
-	if (self->health <= -100)
+	if (b->health <= -100)
 	{
 		addTeleportStars(self);
 		addTeleportStars(tankTrack);
 
 		playSound(SND_APPEAR, CH_ANY);
 
-		self->alive = tankTrack->alive = ALIVE_DEAD;
+		b->alive = tankTrack->alive = ALIVE_DEAD;
 
-		updateObjective(self->name);
+		updateObjective(b->name);
 
-		addDefeatedTarget(self->name);
+		addDefeatedTarget(b->name);
 
 		game.enemiesKilled++;
 	}
@@ -308,7 +349,7 @@ static void applyDamage(int amount)
 	}
 }
 
-static SDL_Rect getBounds(void)
+static SDL_Rect *getBounds(void)
 {
 	if (self->facing == FACING_LEFT)
 	{
@@ -325,5 +366,5 @@ static SDL_Rect getBounds(void)
 		self->bounds.h = self->h;
 	}
 
-	return self->bounds;
+	return &self->bounds;
 }
diff --git a/src/world/entities/boss/tankCommander.h b/src/world/entities/boss/tankCommander.h
index 623ca75..5e5ee10 100644
--- a/src/world/entities/boss/tankCommander.h
+++ b/src/world/entities/boss/tankCommander.h
@@ -31,7 +31,7 @@ extern int enemyCanSeePlayer(Entity *e);
 extern void addDefeatedTarget(char *name);
 extern void updateObjective(char *targetName);
 extern void playSound(int snd, int ch);
-extern Bullet *createBaseBullet(Entity *owner);
+extern Bullet *createBaseBullet(Unit *owner);
 extern void getSlope(int x1, int y1, int x2, int y2, float *dx, float *dy);
 extern void addExplosion(float x, float y, int radius, Entity *owner);
 extern void addScorchDecal(int x, int y);
diff --git a/src/world/entities/boss/tankTrack.c b/src/world/entities/boss/tankTrack.c
index ca13155..036d564 100644
--- a/src/world/entities/boss/tankTrack.c
+++ b/src/world/entities/boss/tankTrack.c
@@ -23,7 +23,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 static Entity *tankCommander;
 static void tick(void);
 static void touch(Entity *other);
-static SDL_Rect getBounds(void);
+static SDL_Rect *getBounds(void);
 static void animate(void);
 static void (*superAnimate)(void);
 
@@ -72,7 +72,7 @@ static void touch(Entity *other)
 {
 	if (other != NULL)
 	{
-		if (other == world.bob && !world.bob->stunTimer && (world.bob->flags & EF_IMMUNE) == 0)
+		if (other == (Entity*)world.bob && !world.bob->stunTimer && (world.bob->flags & EF_IMMUNE) == 0)
 		{
 			playSound(SND_FLESH_HIT, CH_ANY);
 			world.bob->dx = rrnd(-5, 5);
@@ -88,14 +88,14 @@ static void touch(Entity *other)
 	}
 }
 
-static SDL_Rect getBounds(void)
+static SDL_Rect *getBounds(void)
 {
 	self->bounds.x = self->x + 16;
 	self->bounds.y = self->y;
 	self->bounds.w = self->w - 32;
 	self->bounds.h = self->h;
 
-	return self->bounds;
+	return &self->bounds;
 }
 
 static void animate(void)
diff --git a/src/world/entities/cannons/cannon.c b/src/world/entities/cannons/cannon.c
index e4d39ac..f4798da 100644
--- a/src/world/entities/cannons/cannon.c
+++ b/src/world/entities/cannons/cannon.c
@@ -24,36 +24,40 @@ static void applyDamage(int damage);
 static void walk(void);
 static void die(void);
 static void animate(void);
-static SDL_Rect getBounds(void);
+static SDL_Rect *getBounds(void);
 static int canFire(Entity *target);
 static void preFire(void);
 
 void initCannon(Entity *e)
 {
+	Unit *u;
+	
 	initUnit(e);
+	
+	u = (Unit*)self;
 
-	e->sprite[FACING_LEFT] = getSpriteIndex("CannonLeft");
-	e->sprite[FACING_RIGHT] = getSpriteIndex("CannonRight");
-	e->sprite[FACING_DIE] = getSpriteIndex("CannonLeft");
+	u->sprite[FACING_LEFT] = getSpriteIndex("CannonLeft");
+	u->sprite[FACING_RIGHT] = getSpriteIndex("CannonRight");
+	u->sprite[FACING_DIE] = getSpriteIndex("CannonLeft");
 
-	e->weaponType = WPN_MISSILE;
+	u->weaponType = WPN_MISSILE;
 
-	e->maxShotsToFire = 4;
+	u->maxShotsToFire = 4;
 
-	e->reload = 0;
+	u->reload = 0;
 
-	e->canCarryItem = 1;
+	u->canCarryItem = 1;
 
-	e->health = e->healthMax = 50;
+	u->health = u->healthMax = 50;
 
-	e->flags |= EF_EXPLODES;
+	u->flags |= EF_EXPLODES;
 
-	e->animate = animate;
-	e->applyDamage = applyDamage;
-	e->walk = walk;
-	e->die = die;
-	e->getBounds= getBounds;
-	e->canFire = canFire;
+	u->animate = animate;
+	u->applyDamage = applyDamage;
+	u->walk = walk;
+	u->die = die;
+	u->getBounds= getBounds;
+	u->canFire = canFire;
 }
 
 static void applyDamage(int damage)
@@ -70,28 +74,31 @@ static void applyDamage(int damage)
 
 static void die(void)
 {
+	Unit *u;
 	int mx, my;
+	
+	u = (Unit*)self;
 
-	self->health--;
+	u->health--;
 
-	if (self->health % 3 == 0)
+	if (u->health % 3 == 0)
 	{
-		mx = (int) ((self->x + (self->w / 2)) / MAP_TILE_SIZE);
-		my = (int) ((self->y + self->h) / MAP_TILE_SIZE);
+		mx = (int) ((u->x + (u->w / 2)) / MAP_TILE_SIZE);
+		my = (int) ((u->y + u->h) / MAP_TILE_SIZE);
 		addScorchDecal(mx, my);
 
-		addExplosion(self->x, self->y, 50, self);
+		addExplosion(u->x, u->y, 50, self);
 	}
 
-	if (self->health <= -50)
+	if (u->health <= -50)
 	{
-		updateObjective(self->name);
+		updateObjective(u->name);
 		updateObjective("ENEMY");
-		fireTriggers(self->name);
+		fireTriggers(u->name);
 
 		dropCarriedItem();
 
-		self->alive = ALIVE_DEAD;
+		u->alive = ALIVE_DEAD;
 	}
 }
 
@@ -104,9 +111,12 @@ static void patrol(void)
 
 static void lookForPlayer(void)
 {
+	Unit *u;
 	int r;
+	
+	u = (Unit*)self;
 
-	self->thinkTime = rrnd(FPS / 2, FPS);
+	u->thinkTime = rrnd(FPS / 2, FPS);
 
 	if (world.state != WS_IN_PROGRESS || dev.cheatBlind)
 	{
@@ -114,13 +124,13 @@ static void lookForPlayer(void)
 		return;
 	}
 
-	if ((self->facing == FACING_LEFT && world.bob->x > self->x) || (self->facing == FACING_RIGHT && world.bob->x < self->x))
+	if ((u->facing == FACING_LEFT && world.bob->x > u->x) || (u->facing == FACING_RIGHT && world.bob->x < u->x))
 	{
 		patrol();
 		return;
 	}
 
-	if (getDistance(world.bob->x, world.bob->y, self->x, self->y) > 650)
+	if (getDistance(world.bob->x, world.bob->y, u->x, u->y) > 650)
 	{
 		patrol();
 		return;
@@ -134,34 +144,38 @@ static void lookForPlayer(void)
 
 	r = rand() % 100;
 
-	if (self->isMissionTarget)
+	if (u->isMissionTarget)
 	{
 		r = rand() % 20;
 	}
 
 	if (r < 15)
 	{
-		self->shotsToFire = rrnd(1, self->maxShotsToFire);
-		self->action = preFire;
+		u->shotsToFire = rrnd(1, u->maxShotsToFire);
+		u->action = preFire;
 	}
 }
 
 static void preFire(void)
 {
-	self->facing = (world.bob->x < self->x) ? FACING_LEFT : FACING_RIGHT;
+	Unit *u;
+	
+	u = (Unit*)self;
+	
+	u->facing = (world.bob->x < u->x) ? FACING_LEFT : FACING_RIGHT;
 
-	if (self->reload > 0)
+	if (u->reload > 0)
 	{
 		return;
 	}
 
-	self->attack();
+	u->attack();
 
-	self->shotsToFire--;
+	u->shotsToFire--;
 
-	if (self->shotsToFire == 0)
+	if (u->shotsToFire == 0)
 	{
-		self->walk();
+		u->walk();
 	}
 }
 
@@ -175,14 +189,14 @@ static void animate(void)
 
 }
 
-static SDL_Rect getBounds(void)
+static SDL_Rect *getBounds(void)
 {
 	self->bounds.x = self->x + 36;
 	self->bounds.y = self->y;
 	self->bounds.w = 36;
 	self->bounds.h = self->h;
 
-	return self->bounds;
+	return &self->bounds;
 }
 
 static int canFire(Entity *target)
diff --git a/src/world/entities/decoration/debris.c b/src/world/entities/decoration/debris.c
index fde7a09..47ba65a 100644
--- a/src/world/entities/decoration/debris.c
+++ b/src/world/entities/decoration/debris.c
@@ -26,15 +26,19 @@ static void touch(Entity *other);
 
 void initDebris(Entity *e)
 {
+	Decoration *d;
+	
 	initEntity(e);
 	
-	e->effectType = rand() % 2;
+	d = (Decoration*)self;
+	
+	d->effectType = rand() % 2;
 
-	e->flags |= EF_BOUNCES | EF_IGNORE_BULLETS | EF_KILL_OFFSCREEN | EF_NO_TELEPORT;
+	d->flags |= EF_BOUNCES | EF_IGNORE_BULLETS | EF_KILL_OFFSCREEN | EF_NO_TELEPORT;
 
-	e->tick = tick;
-	e->action = action;
-	e->touch = touch;
+	d->tick = tick;
+	d->action = action;
+	d->touch = touch;
 }
 
 static void tick(void)
@@ -44,13 +48,17 @@ static void tick(void)
 
 static void action(void)
 {
-	if (self->effectType == 0)
+	Decoration *d;
+	
+	d = (Decoration*)self;
+	
+	if (d->effectType == 0)
 	{
-		addFlameParticles(self->x + (rand() % self->w), self->y + (rand() % self->h));
+		addFlameParticles(d->x + (rand() % d->w), d->y + (rand() % d->h));
 	}
 	else
 	{
-		addSmokeParticles(self->x + (rand() % self->w), self->y + (rand() % self->h));
+		addSmokeParticles(d->x + (rand() % d->w), d->y + (rand() % d->h));
 	}
 
 	self->thinkTime = 1;
@@ -58,8 +66,12 @@ static void action(void)
 
 static void touch(Entity *other)
 {
+	Decoration *d;
+	
+	d = (Decoration*)self;
+	
 	if (other == NULL)
 	{
-		self->dx *= 0.9;
+		d->dx *= 0.9;
 	}
 }
diff --git a/src/world/entities/decoration/fleshChunk.c b/src/world/entities/decoration/fleshChunk.c
index 8d6ce6e..93860b3 100644
--- a/src/world/entities/decoration/fleshChunk.c
+++ b/src/world/entities/decoration/fleshChunk.c
@@ -26,31 +26,43 @@ static void touch(Entity *other);
 
 void initFleshChunk(Entity *e)
 {
+	Decoration *d;
+	
 	initEntity(e);
+	
+	d = (Decoration*)e;
 
-	e->flags |= EF_BOUNCES | EF_IGNORE_BULLETS | EF_KILL_OFFSCREEN | EF_NO_TELEPORT;
+	d->flags |= EF_BOUNCES | EF_IGNORE_BULLETS | EF_KILL_OFFSCREEN | EF_NO_TELEPORT;
 
-	e->bleedTime = FPS * 3;
+	d->bleedTime = FPS * 3;
 
-	e->tick = tick;
-	e->action = action;
-	e->touch = touch;
+	d->tick = tick;
+	d->action = action;
+	d->touch = touch;
 }
 
 static void tick(void)
 {
-	self->health--;
-	self->bleedTime--;
+	Decoration *d;
+	
+	d = (Decoration*)self;
+	
+	d->health--;
+	d->bleedTime--;
 }
 
 static void action(void)
 {
-	if (self->bleedTime > 0)
+	Decoration *d;
+	
+	d = (Decoration*)self;
+	
+	if (d->bleedTime > 0)
 	{
-		addBlood(self->x + (rand() % self->w), self->y + (rand() % self->h));
+		addBlood(d->x + (rand() % d->w), d->y + (rand() % d->h));
 	}
 
-	self->thinkTime = 1;
+	d->thinkTime = 1;
 }
 
 static void touch(Entity *other)
diff --git a/src/world/entities/entities.c b/src/world/entities/entities.c
index 37ac4b4..3c511da 100644
--- a/src/world/entities/entities.c
+++ b/src/world/entities/entities.c
@@ -22,16 +22,71 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 void animateEntity(void);
 static void applyDamage(int damage);
+static float bounce(float x);
+static SDL_Rect *getBounds(void);
 
-Entity *createEntity(void)
+Entity *createEntity(int type)
 {
 	Entity *e;
 	
-	e = malloc(sizeof(Entity));
-	memset(e, 0, sizeof(Entity));
+	switch (type)
+	{
+		case ET_BOB:
+			e = malloc(sizeof(Bob));
+			memset(e, 0, sizeof(Bob));
+			break;
+		
+		case ET_ENEMY:
+		case ET_TEEKA:
+			e = malloc(sizeof(Unit));
+			memset(e, 0, sizeof(Unit));
+			break;
+			
+		case ET_BOSS:
+			e = malloc(sizeof(Boss));
+			memset(e, 0, sizeof(Boss));
+			break;
+		
+		case ET_HEART_CELL:
+		case ET_KEY:
+		case ET_ITEM:
+		case ET_CONSUMABLE:
+			e = malloc(sizeof(Item));
+			memset(e, 0, sizeof(Item));
+			break;
+		
+		case ET_MIA:
+			e = malloc(sizeof(MIA));
+			memset(e, 0, sizeof(MIA));
+			break;
+		
+		case ET_DECORATION:
+			e = malloc(sizeof(Decoration));
+			memset(e, 0, sizeof(Decoration));
+			break;
+			
+		case ET_DOOR:
+		case ET_LIFT:
+		case ET_PUSHBLOCK:
+		case ET_DESTRUCTABLE:
+		case ET_POWER_POINT:
+		case ET_CARD_READER:
+		case ET_PRESSURE_PLATE:
+		case ET_TELEPORTER:
+		case ET_ITEM_PAD:
+		case ET_POOL:
+		case ET_TRAP:
+		case ET_EXIT:
+		case ET_INFO_POINT:
+			e = malloc(sizeof(Structure));
+			memset(e, 0, sizeof(Structure));
+			break;
+	}
+	
 	world.entityTail->next = e;
 	world.entityTail = e;
 	
+	e->type = type;
 	e->uniqueId = game.entityCounter++;
 	
 	return e;
@@ -49,38 +104,31 @@ void initEntity(Entity *e)
 	e->isStatic = 0;
 	e->isMissionTarget = 0;
 
-	e->health = e->healthMax = 1;
+	e->health = 1;
 
 	e->facing = FACING_LEFT;
 
-	e->spriteFrame = -1;
-	e->spriteTime = 0;
-
-	e->dx = e->dy = 0;
-
 	e->flags = 0;
 
-	e->owner = NULL;
-
 	e->thinkTime = 0;
-
-	e->plane = PLANE_BACKGROUND;
 	
 	e->animate = animateEntity;
 	e->applyDamage = applyDamage;
+	e->bounce = bounce;
+	e->getBounds = getBounds;
 }
 
-SDL_Rect *getEntityBounds(Entity *e)
+static SDL_Rect *getBounds(void)
 {
-	e->bounds.x = e->x;
-	e->bounds.y = e->y;
-	e->bounds.w = e->w;
-	e->bounds.h = e->h;
+	self->bounds.x = self->x;
+	self->bounds.y = self->y;
+	self->bounds.w = self->w;
+	self->bounds.h = self->h;
 
-	return &e->bounds;
+	return &self->bounds;
 }
 
-int getCurrentEntitySprite(Entity *e)
+int getCurrentEntitySprite(EntityExt *e)
 {
 	if (e->alive == ALIVE_ALIVE)
 	{
@@ -92,39 +140,19 @@ int getCurrentEntitySprite(Entity *e)
 
 void animateEntity(void)
 {
-	Sprite *spr;
-	
-	if (self->spriteTime != -1)
-	{
-		self->spriteTime--;
-
-		if (self->spriteTime <= 0)
-		{
-			spr = getSpriteByIndex(getCurrentEntitySprite(self));
-			self->spriteFrame = wrap(self->spriteFrame + 1, 0, 1);
-			self->spriteTime = 0;
-			self->w = spr->w;
-			self->h = spr->h;
-		}
-	}
 }
 
 void setEntitySize(Entity *e)
 {
-	Sprite *spr;
-	
-	spr = getSpriteByIndex(getCurrentEntitySprite(e));
-	e->w = spr->w;
-	e->h = spr->h;
 }
 
-float bounce(Entity *e, float x)
+static float bounce(float x)
 {
-	if (!(e->flags & EF_BOUNCES))
+	if (!(self->flags & EF_BOUNCES))
 	{
 		return 0;
 	}
-	else if (e->flags & EF_FRICTIONLESS)
+	else if (self->flags & EF_FRICTIONLESS)
 	{
 		return -x;
 	}
@@ -133,7 +161,7 @@ float bounce(Entity *e, float x)
 
 	if (x > -1 && x < 1)
 	{
-		e->flags &= ~EF_BOUNCES;
+		self->flags &= ~EF_BOUNCES;
 		x = 0;
 	}
 
@@ -160,27 +188,29 @@ void teleportEntity(Entity *e, float tx, float ty)
 
 static void applyDamage(int damage)
 {
-	if (self->health < 0)
+	
+}
+
+void dropCarriedItem(void)
+{
+	EntityExt *e;
+	Item *i;
+	
+	e = (EntityExt*)self;
+	
+	if (e->carriedItem != NULL)
 	{
-		self->health = 0;
-		self->alive = ALIVE_ALIVE;
-	}
+		i = e->carriedItem;
+		
+		i->x = (e->x + e->w / 2) - i->w / 2;
+		i->y = e->y;
 
-	self->health -= damage;
+		i->dx = i->dy = 0;
 
-	if (self->health > 0)
-	{
-		self->thinkTime = 0;
+		world.entityTail->next = (Entity*)i;
+		world.entityTail = (Entity*)i;
+		world.entityTail->next = NULL;
 
-		self->facing = self->x < world.bob->x ? FACING_RIGHT : FACING_LEFT;
-
-		if (self->isMissionTarget && rand() % 10 == 0)
-		{
-			self->action = unitReappear;
-			self->flags |= EF_GONE;
-			self->thinkTime = rand() % FPS;
-			addTeleportStars(self);
-			playSound(SND_APPEAR, CH_ANY);
-		}
+		e->carriedItem = NULL;
 	}
 }
diff --git a/src/world/entities/items/battery.c b/src/world/entities/items/battery.c
index 4bbdd60..f4c7712 100644
--- a/src/world/entities/items/battery.c
+++ b/src/world/entities/items/battery.c
@@ -22,19 +22,27 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 void initBattery(Entity *e)
 {
+	Item *i;
+	
 	initConsumable(e);
+	
+	i = (Item*)e;
 
-	e->spriteFrame = 0;
-	e->spriteTime = -1;
+	i->spriteFrame = 0;
+	i->spriteTime = -1;
 }
 
 void touch(Entity *other)
 {
+	Item *i;
+	
+	i = (Item*)self;
+	
 	if (touchedPlayer(other))
 	{
-		world.bob->power = MIN(world.bob->power + self->power, world.bob->powerMax);
+		world.bob->power = MIN(world.bob->power + i->power, world.bob->powerMax);
 
-		setGameplayMessage(MSG_STANDARD, "Picked up a %s", self->name);
+		setGameplayMessage(MSG_STANDARD, "Picked up a %s", i->name);
 
 		pickupItem();
 
diff --git a/src/world/entities/items/cell.c b/src/world/entities/items/cell.c
index 0ea6c50..84f75a9 100644
--- a/src/world/entities/items/cell.c
+++ b/src/world/entities/items/cell.c
@@ -24,18 +24,22 @@ static void touch(Entity *other);
 
 void initCell(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)self;
 
-	e->isMissionTarget = 1;
+	i->isMissionTarget = 1;
 
-	STRNCPY(e->spriteName, "Battery", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "Battery", MAX_NAME_LENGTH);
 
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("Battery");
+	i->sprite[0] = i->sprite[1] = i->sprite[2] = getSpriteIndex("Battery");
 
-	e->spriteFrame = 0;
-	e->spriteTime = -1;
+	i->spriteFrame = 0;
+	i->spriteTime = -1;
 
-	e->touch = touch;
+	i->touch = touch;
 }
 
 static void touch(Entity *other)
diff --git a/src/world/entities/items/cherry.c b/src/world/entities/items/cherry.c
index c028617..3d180ac 100644
--- a/src/world/entities/items/cherry.c
+++ b/src/world/entities/items/cherry.c
@@ -31,11 +31,15 @@ void initCherry(Entity *e)
 
 static void touch(Entity *other)
 {
+	Item *i;
+	
+	i = (Item*)self;
+	
 	if (touchedPlayer(other))
 	{
-		world.bob->health = limit(world.bob->health + self->value, 0, world.bob->healthMax);
+		world.bob->health = limit(world.bob->health + i->value, 0, world.bob->healthMax);
 
-		setGameplayMessage(MSG_STANDARD, "Picked up a %s", self->name);
+		setGameplayMessage(MSG_STANDARD, "Picked up a %s", i->name);
 
 		pickupItem();
 
diff --git a/src/world/entities/items/consumable.c b/src/world/entities/items/consumable.c
index 6fda820..0c8b086 100644
--- a/src/world/entities/items/consumable.c
+++ b/src/world/entities/items/consumable.c
@@ -35,20 +35,24 @@ void initConsumable(Entity *e)
 
 static void tick(void)
 {
-	if (self->isOnGround)
+	Item *i;
+	
+	i = (Item*)self;
+	
+	if (i->isOnGround)
 	{
-		self->dx *= 0.05;
+		i->dx *= 0.05;
 	}
 
-	self->health--;
+	i->health--;
 
-	if ((int) self->health == FPS * 2)
+	if ((int) i->health == FPS * 2)
 	{
-		self->flags |= EF_FLICKER;
+		i->flags |= EF_FLICKER;
 	}
-	else if (self->health <= 0)
+	else if (i->health <= 0)
 	{
-		self->alive = ALIVE_DEAD;
+		i->alive = ALIVE_DEAD;
 	}
 }
 
@@ -59,12 +63,16 @@ int touchedPlayer(Entity *other)
 
 void pickupItem(void)
 {
-	self->alive = (self->environment == ENV_AIR) ? ALIVE_DYING : ALIVE_DEAD;
-	self->health = FPS / 2;
-	self->thinkTime = 0;
-	self->dy = -2;
-	self->dx = 0;
-	self->flags |= EF_FLICKER | EF_WEIGHTLESS;
+	Item *i;
+	
+	i = (Item*)self;
+	
+	i->alive = (i->environment == ENV_AIR) ? ALIVE_DYING : ALIVE_DEAD;
+	i->health = FPS / 2;
+	i->thinkTime = 0;
+	i->dy = -2;
+	i->dx = 0;
+	i->flags |= EF_FLICKER | EF_WEIGHTLESS;
 }
 
 static void die(void)
diff --git a/src/world/entities/items/heart.c b/src/world/entities/items/heart.c
index 0767191..413f84a 100644
--- a/src/world/entities/items/heart.c
+++ b/src/world/entities/items/heart.c
@@ -25,19 +25,23 @@ static void touch(Entity *other);
 
 void initHeart(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	e->isMissionTarget = 1;
+	i->isMissionTarget = 1;
 
-	STRNCPY(e->spriteName, "Heart", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "Heart", MAX_NAME_LENGTH);
 
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("Heart");
+	i->sprite[0] = i->sprite[1] = i->sprite[2] = getSpriteIndex("Heart");
 
-	e->spriteFrame = 0;
-	e->spriteTime = -1;
+	i->spriteFrame = 0;
+	i->spriteTime = -1;
 
-	e->action = action;
-	e->touch = touch;
+	i->action = action;
+	i->touch = touch;
 }
 
 static void action(void)
diff --git a/src/world/entities/items/item.c b/src/world/entities/items/item.c
index a34b288..fe387f4 100644
--- a/src/world/entities/items/item.c
+++ b/src/world/entities/items/item.c
@@ -25,36 +25,44 @@ static void tick(void);
 static void touch(Entity *other);
 static void changeEnvironment(void);
 static void die(void);
-static void destructablePickupItem(Entity *e);
-static void enemyPickupItem(Entity *e);
+static void destructablePickupItem(Structure *s);
+static void enemyPickupItem(Unit *u);
 static void bobPickupItem(void);
 
 void initItem(Entity *e)
 {
+	Item *i;
+	
 	initEntity(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->spriteName, "Weapon", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "Weapon", MAX_NAME_LENGTH);
 
-	e->flags |= EF_IGNORE_BULLETS;
+	i->flags |= EF_IGNORE_BULLETS;
 
-	e->isMissionTarget = 1;
-	e->canBePickedUp = 1;
-	e->canBeCarried = 0;
-	e->collected = 0;
+	i->isMissionTarget = 1;
+	i->canBePickedUp = 1;
+	i->canBeCarried = 0;
+	i->collected = 0;
 
-	e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex(e->spriteName);
+	i->sprite[FACING_LEFT] = i->sprite[FACING_RIGHT] = i->sprite[FACING_DIE] = getSpriteIndex(i->spriteName);
 
-	e->tick = tick;
-	e->touch = touch;
-	e->changeEnvironment = changeEnvironment;
-	e->reset = reset;
-	e->die = die;
+	i->tick = tick;
+	i->touch = touch;
+	i->changeEnvironment = changeEnvironment;
+	i->reset = reset;
+	i->die = die;
 }
 
 static void reset(void)
 {
-	self->startX = (int) self->x;
-	self->startY = (int) self->y;
+	Item *i;
+	
+	i = (Item*)self;
+	
+	i->startX = (int) self->x;
+	i->startY = (int) self->y;
 }
 
 static void tick(void)
@@ -70,7 +78,11 @@ static void tick(void)
 
 static void touch(Entity *other)
 {
-	if (self->alive == ALIVE_ALIVE && other != NULL && self->canBePickedUp)
+	Item *i;
+	
+	i = (Item*)self;
+	
+	if (i->alive == ALIVE_ALIVE && other != NULL && i->canBePickedUp)
 	{
 		if (other->type == ET_BOB && !world.bob->stunTimer)
 		{
@@ -78,27 +90,31 @@ static void touch(Entity *other)
 		}
 		else if (other->type == ET_ENEMY)
 		{
-			enemyPickupItem(other);
+			enemyPickupItem((Unit*)other);
 		}
 		else if (other->type == ET_DESTRUCTABLE)
 		{
-			destructablePickupItem(other);
+			destructablePickupItem((Structure*)other);
 		}
 	}
 }
 
 static void bobPickupItem(void)
 {
-	if (!self->isMissionTarget)
+	Item *i;
+	
+	i = (Item*)self;
+	
+	if (!i->isMissionTarget)
 	{
-		if (self->thinkTime == 0)
+		if (i->thinkTime == 0)
 		{
-			self->alive = ALIVE_DEAD;
-			addKey(self->name);
+			i->alive = ALIVE_DEAD;
+			addKey(i->name);
 			game.keysFound++;
 			updateObjective("KEY");
 
-			setGameplayMessage(MSG_STANDARD, "Picked up a %s", self->name);
+			setGameplayMessage(MSG_STANDARD, "Picked up a %s", i->name);
 
 			playSound(SND_KEY, CH_ITEM);
 		}
@@ -107,21 +123,21 @@ static void bobPickupItem(void)
 			setGameplayMessage(MSG_GAMEPLAY, "Can't carry any more keys");
 		}
 	}
-	else if (self->canBeCarried)
+	else if (i->canBeCarried)
 	{
 		if (numCarriedItems() < MAX_ITEMS)
 		{
-			self->flags |= EF_GONE;
+			i->flags |= EF_GONE;
 
-			if (!self->collected)
+			if (!i->collected)
 			{
-				updateObjective(self->name);
-				self->collected = 1;
+				updateObjective(i->name);
+				i->collected = 1;
 			}
 
-			addBobItem(self);
+			addBobItem(i);
 			
-			setGameplayMessage(MSG_STANDARD, "Picked up a %s", self->name);
+			setGameplayMessage(MSG_STANDARD, "Picked up a %s", i->name);
 
 			playSound(SND_ITEM, CH_ITEM);
 		}
@@ -132,45 +148,57 @@ static void bobPickupItem(void)
 	}
 	else
 	{
-		self->alive = ALIVE_DEAD;
-		updateObjective(self->name);
+		i->alive = ALIVE_DEAD;
+		updateObjective(i->name);
 
 		if (strcmp(world.id, "teeka") != 0)
 		{
-			setGameplayMessage(MSG_STANDARD, "Picked up a %s", self->name);
+			setGameplayMessage(MSG_STANDARD, "Picked up a %s", i->name);
 		}
 
 		playSound(SND_ITEM, CH_ITEM);
 	}
 }
 
-static void enemyPickupItem(Entity *e)
+static void enemyPickupItem(Unit *u)
 {
-	if (e->canCarryItem && e->carriedItem == NULL && e->alive == ALIVE_ALIVE)
+	Item *i;
+	
+	i = (Item*)self;
+	
+	if (u->canCarryItem && u->carriedItem == NULL && u->alive == ALIVE_ALIVE)
 	{
-		e->carriedItem = self;
+		u->carriedItem = i;
 
-		self->flags |= EF_GONE;
+		i->flags |= EF_GONE;
 	}
 }
 
-static void destructablePickupItem(Entity *e)
+static void destructablePickupItem(Structure *s)
 {
-	if (e->carriedItem == NULL && e->alive == ALIVE_ALIVE)
+	Item *i;
+	
+	i = (Item*)self;
+	
+	if (s->carriedItem == NULL && s->alive == ALIVE_ALIVE)
 	{
-		e->carriedItem = self;
+		s->carriedItem = i;
 
-		self->flags |= EF_GONE;
+		i->flags |= EF_GONE;
 	}
 }
 
 static void changeEnvironment(void)
 {
-	if (self->environment == ENV_SLIME || self->environment == ENV_LAVA)
+	Item *i;
+	
+	i = (Item*)self;
+	
+	if (i->environment == ENV_SLIME || i->environment == ENV_LAVA)
 	{
 		addTeleportStars(self);
-		self->x = self->startX;
-		self->y = self->startY;
+		i->x = i->startX;
+		i->y = i->startY;
 		addTeleportStars(self);
 		playSound(SND_APPEAR, CH_ANY);
 	}
diff --git a/src/world/entities/items/item.h b/src/world/entities/items/item.h
index fae5c53..ee8761f 100644
--- a/src/world/entities/items/item.h
+++ b/src/world/entities/items/item.h
@@ -25,7 +25,7 @@ extern void setGameplayMessage(int type, char *format, ...);
 extern void addTeleportStars(Entity *e);
 extern void initEntity(Entity *e);
 extern int getSpriteIndex(char *name);
-extern void addBobItem(Entity *e);
+extern void addBobItem(Item *i);
 extern int numCarriedItems(void);
 extern void addKey(char *name);
 extern void updateObjective(char *targetName);
diff --git a/src/world/entities/items/key.c b/src/world/entities/items/key.c
index b9bca38..7bc4cbe 100644
--- a/src/world/entities/items/key.c
+++ b/src/world/entities/items/key.c
@@ -22,24 +22,36 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 void initBronzeKey(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "Bronze Key", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "BronzeKey", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "Bronze Key", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "BronzeKey", MAX_NAME_LENGTH);
 }
 
 void initSilverKey(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "Silver Key", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "SilverKey", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "Silver Key", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "SilverKey", MAX_NAME_LENGTH);
 }
 
 void initGoldKey(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "Gold Key", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "GoldKey", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "Gold Key", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "GoldKey", MAX_NAME_LENGTH);
 }
diff --git a/src/world/entities/items/keycard.c b/src/world/entities/items/keycard.c
index b19c03b..fa19c49 100644
--- a/src/world/entities/items/keycard.c
+++ b/src/world/entities/items/keycard.c
@@ -25,53 +25,73 @@ static void touchWhiteKeycard(Entity *other);
 
 void initRedKeycard(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "Red Keycard", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "RedKeycard", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "Red Keycard", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "RedKeycard", MAX_NAME_LENGTH);
 }
 
 void initBlueKeycard(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "Blue Keycard", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "BlueKeycard", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "Blue Keycard", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "BlueKeycard", MAX_NAME_LENGTH);
 }
 
 void initGreenKeycard(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "Green Keycard", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "GreenKeycard", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "Green Keycard", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "GreenKeycard", MAX_NAME_LENGTH);
 }
 
 void initYellowKeycard(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "Yellow Keycard", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "YellowKeycard", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "Yellow Keycard", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "YellowKeycard", MAX_NAME_LENGTH);
 }
 
 void initWhiteKeycard(Entity *e)
 {
+	Item *i;
+	
 	initItem(e);
+	
+	i = (Item*)e;
 
-	STRNCPY(e->name, "White Keycard", MAX_NAME_LENGTH);
-	STRNCPY(e->spriteName, "WhiteKeycard", MAX_NAME_LENGTH);
+	STRNCPY(i->name, "White Keycard", MAX_NAME_LENGTH);
+	STRNCPY(i->spriteName, "WhiteKeycard", MAX_NAME_LENGTH);
 
-	itemTouch = e->touch;
+	itemTouch = i->touch;
 
-	e->touch = touchWhiteKeycard;
+	i->touch = touchWhiteKeycard;
 }
 
 static void touchWhiteKeycard(Entity *other)
 {
 	itemTouch(other);
 
-	if (other == world.bob)
+	if (other == (Entity*)world.bob)
 	{
 		updateObjective("White Keycard");
 
diff --git a/src/world/entities/items/weaponPickup.c b/src/world/entities/items/weaponPickup.c
index f8ebeea..1906bc9 100644
--- a/src/world/entities/items/weaponPickup.c
+++ b/src/world/entities/items/weaponPickup.c
@@ -34,51 +34,63 @@ static char *description[] = {
 
 void initWeaponPickup(Entity *e)
 {
+	Item *i;
+	
 	initConsumable(e);
+	
+	i = (Item*)e;
 
-	e->weaponType = WPN_PISTOL;
+	i->weaponType = WPN_PISTOL;
 
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("Weapon");
-	e->spriteFrame = e->weaponType;
-	e->spriteTime = -1;
+	i->sprite[0] = i->sprite[1] = i->sprite[2] = getSpriteIndex("Weapon");
+	i->spriteFrame = i->weaponType;
+	i->spriteTime = -1;
 	
 	setEntitySize(e);
 
-	if (e->provided)
+	if (i->provided)
 	{
-		e->health = 9999;
+		i->health = 9999;
 	}
 
-	itemTick = e->tick;
+	itemTick = i->tick;
 
-	e->tick = tick;
-	e->touch = touch;
+	i->tick = tick;
+	i->touch = touch;
 }
 
 static void tick(void)
 {
+	Item *i;
+	
+	i = (Item*)self;
+	
 	itemTick();
 
-	if (self->provided && self->alive == ALIVE_ALIVE)
+	if (i->provided && i->alive == ALIVE_ALIVE)
 	{
-		self->health = 9999;
+		i->health = 9999;
 	}
 }
 
 static void touch(Entity *other)
 {
+	Item *i;
+	
+	i = (Item*)self;
+	
 	if (touchedPlayer(other))
 	{
-		world.bob->weaponType = self->weaponType;
+		world.bob->weaponType = i->weaponType;
 
-		switch (self->weaponType)
+		switch (i->weaponType)
 		{
 			case WPN_GRENADES:
 				setGameplayMessage(MSG_STANDARD, "Got some Grenades");
 				break;
 
 			default:
-				setGameplayMessage(MSG_STANDARD, "Picked up a %s", description[self->weaponType]);
+				setGameplayMessage(MSG_STANDARD, "Picked up a %s", description[i->weaponType]);
 				break;
 		}
 
diff --git a/src/world/entities/misc/destructable.c b/src/world/entities/misc/destructable.c
index 4aae5d7..64eb53d 100644
--- a/src/world/entities/misc/destructable.c
+++ b/src/world/entities/misc/destructable.c
@@ -25,20 +25,24 @@ static void action(void);
 
 void initDestructable(Entity *e)
 {
+	Structure *s;
+	
 	initEntity(e);
 	
-	e->isMissionTarget = 1;
-
-	STRNCPY(e->spriteName, "Crate4", MAX_NAME_LENGTH);
-
-	e->flags |= EF_EXPLODES;
-
-	e->health = e->healthMax = 10;
+	s = (Structure*)e;
 	
-	e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex(e->spriteName);
+	s->isMissionTarget = 1;
+
+	STRNCPY(s->spriteName, "Crate4", MAX_NAME_LENGTH);
+
+	s->flags |= EF_EXPLODES;
+
+	s->health = s->healthMax = 10;
 	
-	e->applyDamage = applyDamage;
-	e->action = action;
+	s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex(s->spriteName);
+	
+	s->applyDamage = applyDamage;
+	s->action = action;
 }
 
 static void applyDamage(int amount)
@@ -51,35 +55,38 @@ static void applyDamage(int amount)
 
 static void action(void)
 {
+	Structure *s;
 	int mx, my;
 	
-	if (self->health <= 0)
+	s = (Structure*)self;
+	
+	if (s->health <= 0)
 	{
-		self->health--;
+		s->health--;
 
-		if (self->health % 3 == 0)
+		if (s->health % 3 == 0)
 		{
-			mx = (int) ((self->x + (self->w / 2)) / MAP_TILE_SIZE);
-			my = (int) ((self->y + self->h) / MAP_TILE_SIZE);
+			mx = (int) ((s->x + (s->w / 2)) / MAP_TILE_SIZE);
+			my = (int) ((s->y + s->h) / MAP_TILE_SIZE);
 			addScorchDecal(mx, my);
 
-			addExplosion(self->x, self->y, 50, self);
-			self->dx = rrnd(-10, 10);
-			self->dy = rrnd(-10, 10);
+			addExplosion(s->x, s->y, 50, self);
+			s->dx = rrnd(-10, 10);
+			s->dy = rrnd(-10, 10);
 		}
 
-		if (self->health <= -50)
+		if (s->health <= -50)
 		{
 			dropCarriedItem();
 
-			updateObjective(self->name);
+			updateObjective(s->name);
 
-			if (strlen(self->targetNames) > 0)
+			if (strlen(s->targetNames) > 0)
 			{
-				activateEntities(self->targetNames, 1);
+				activateEntities(s->targetNames, 1);
 			}
 
-			self->alive = ALIVE_DEAD;
+			s->alive = ALIVE_DEAD;
 		}
 	}
 }
diff --git a/src/world/entities/misc/infoPoint.c b/src/world/entities/misc/infoPoint.c
index 439bc42..b3b293f 100644
--- a/src/world/entities/misc/infoPoint.c
+++ b/src/world/entities/misc/infoPoint.c
@@ -25,57 +25,68 @@ static void touch(Entity *other);
 
 void initInfoPoint(Entity *e)
 {
+	Structure *s;
+	
 	initEntity(e);
 	
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("InfoPoint");
-
-	e->flags |= EF_WEIGHTLESS | EF_IGNORE_BULLETS | EF_NO_CLIP | EF_NO_ENVIRONMENT;
+	s = (Structure*)e;
 	
-	e->ty = e->y;
+	s->sprite[0] = s->sprite[1] = s->sprite[2] = getSpriteIndex("InfoPoint");
 
-	e->firstTouch = 1;
+	s->flags |= EF_WEIGHTLESS | EF_IGNORE_BULLETS | EF_NO_CLIP | EF_NO_ENVIRONMENT;
 	
-	e->tick = tick;
-	e->touch = touch;
+	s->ty = s->y;
+
+	s->firstTouch = 1;
+	
+	s->tick = tick;
+	s->touch = touch;
 }
 
 static void tick(void)
 {
-	self->sinVal -= 0.05;
-	self->y += (float) sin(self->sinVal) * 0.1;
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	s->sinVal -= 0.05;
+	s->y += (float) sin(s->sinVal) * 0.1;
 }
 
 static void touch(Entity *other)
 {
+	Structure *s;
 	int showMessage;
 	
-	if (other == world.bob)
+	s = (Structure*)self;
+	
+	if (other == (Entity*)world.bob)
 	{
 		showMessage = 0;
 
-		if (self->firstTouch)
+		if (s->firstTouch)
 		{
-			self->firstTouch = 0;
+			s->firstTouch = 0;
 			showMessage = 1;
-			self->messageTimer = FPS;
+			s->messageTimer = FPS;
 		}
 		else if (world.bob->dx == 0 && world.bob->dy == 0 && world.bob->isOnGround)
 		{
-			self->messageTimer++;
+			s->messageTimer++;
 
-			if (self->messageTimer == FPS)
+			if (s->messageTimer == FPS)
 			{
 				showMessage = 1;
 			}
 		}
 		else
 		{
-			self->messageTimer = 0;
+			s->messageTimer = 0;
 		}
 
 		if (showMessage)
 		{
-			showInfoMessage(self->message);
+			showInfoMessage(s->message);
 		}
 	}
 }
diff --git a/src/world/entities/structures/cardReader.c b/src/world/entities/structures/cardReader.c
index 51dd6b1..4fe7065 100644
--- a/src/world/entities/structures/cardReader.c
+++ b/src/world/entities/structures/cardReader.c
@@ -25,60 +25,72 @@ static void touch(Entity *other);
 
 void initCardReader(Entity *e)
 {
+	Structure *s;
+	
 	initEntity(e);
 	
-	e->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS | EF_NO_TELEPORT;
-
-	STRNCPY(e->requiredCard, "Black Keycard", MAX_NAME_LENGTH);
-
-	e->isStatic = 1;
+	s = (Structure*)e;
 	
-	if (!e->active)
+	s->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS | EF_NO_TELEPORT;
+
+	STRNCPY(s->requiredItem, "Black Keycard", MAX_NAME_LENGTH);
+
+	s->isStatic = 1;
+	
+	if (!s->active)
 	{
-		e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex("CardReaderIdle");
+		s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("CardReaderIdle");
 	}
 	else
 	{
-		e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex("CardReader");
+		s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("CardReader");
 	}
 	
-	e->tick = tick;
-	e->touch = touch;
+	s->tick = tick;
+	s->touch = touch;
 }
 
 static void tick(void)
 {
-	if (!self->active)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (!s->active)
 	{
-		self->bobTouching = MAX(self->bobTouching - 1, 0);
+		s->bobTouching = MAX(s->bobTouching - 1, 0);
 	}
 }
 
 static void touch(Entity *other)
 {
-	if (!self->active && other->type == ET_BOB)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (!s->active && other->type == ET_BOB)
 	{
-		if (hasItem(self->requiredCard) || dev.cheatKeys)
+		if (hasItem(s->requiredItem) || dev.cheatKeys)
 		{
-			activateEntities(self->targetNames, 1);
+			activateEntities(s->targetNames, 1);
 
-			setGameplayMessage(MSG_GAMEPLAY, "%s removed", self->requiredCard);
+			setGameplayMessage(MSG_GAMEPLAY, "%s removed", s->requiredItem);
 
-			removeItem(self->requiredCard);
+			removeItem(s->requiredItem);
 
-			self->active = 1;
-			self->sprite[FACING_LEFT] = self->sprite[FACING_RIGHT] = self->sprite[FACING_DIE] = getSpriteIndex("CardReader");
-			self->spriteTime = 0;
-			self->spriteFrame = 0;
+			s->active = 1;
+			s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("CardReader");
+			s->spriteTime = 0;
+			s->spriteFrame = 0;
 
 			playSound(SND_CONFIRMED, CH_TOUCH);
 		}
-		else if (self->bobTouching == 0)
+		else if (s->bobTouching == 0)
 		{
-			setGameplayMessage(MSG_GAMEPLAY, "%s required", self->requiredCard);
+			setGameplayMessage(MSG_GAMEPLAY, "%s required", s->requiredItem);
 			playSound(SND_DENIED, CH_TOUCH);
 		}
 
-		self->bobTouching = 2;
+		s->bobTouching = 2;
 	}
 }
diff --git a/src/world/entities/structures/door.c b/src/world/entities/structures/door.c
index fe2113f..34592d9 100644
--- a/src/world/entities/structures/door.c
+++ b/src/world/entities/structures/door.c
@@ -29,103 +29,123 @@ static int isClosing(void);
 
 void initDoor(Entity *e)
 {
+	Structure *s;
+	
 	initEntity(e);
 	
-	e->isSolid = 1;
-
-	e->flags |= EF_WEIGHTLESS | EF_NO_ENVIRONMENT | EF_NO_CLIP | EF_EXPLODES | EF_NO_TELEPORT;
-
-	e->closedX = e->closedY = -1;
-
-	e->state = DOOR_CLOSED;
-
-	e->speed = 8;
-
-	e->isLocked = 1;
-
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("Door");
+	s = (Structure*)e;
 	
-	if (e->closedX == -1 && e->closedY == -1)
+	s->isSolid = 1;
+
+	s->flags |= EF_WEIGHTLESS | EF_NO_ENVIRONMENT | EF_NO_CLIP | EF_EXPLODES | EF_NO_TELEPORT;
+
+	s->closedX = s->closedY = -1;
+
+	s->state = DOOR_CLOSED;
+
+	s->speed = 8;
+
+	s->isLocked = 1;
+
+	s->sprite[0] = s->sprite[1] = s->sprite[2] = getSpriteIndex("Door");
+	
+	if (s->closedX == -1 && s->closedY == -1)
 	{
-		e->closedX = (int) e->x;
-		e->closedY = (int) e->y;
+		s->closedX = (int) s->x;
+		s->closedY = (int) s->y;
 	}
 	
-	e->tick = tick;
-	e->touch = touch;
+	s->tick = tick;
+	s->touch = touch;
 }
 
 void initBronzeDoor(Entity *e)
 {
+	Structure *s;
+	
 	initDoor(e);
 	
-	STRNCPY(e->requiredKey, "Bronze Key", MAX_NAME_LENGTH);
+	s = (Structure*)e;
+	
+	STRNCPY(s->requiredItem, "Bronze Key", MAX_NAME_LENGTH);
 
-	e->speed = 2;
+	s->speed = 2;
 
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("BronzeDoor");
+	s->sprite[0] = s->sprite[1] = s->sprite[2] = getSpriteIndex("BronzeDoor");
 }
 
 void initSilverDoor(Entity *e)
 {
+	Structure *s;
+	
 	initDoor(e);
 	
-	STRNCPY(e->requiredKey, "Silver Key", MAX_NAME_LENGTH);
+	s = (Structure*)e;
+	
+	STRNCPY(s->requiredItem, "Silver Key", MAX_NAME_LENGTH);
 
-	e->speed = 2;
+	s->speed = 2;
 
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("SilverDoor");
+	s->sprite[0] = s->sprite[1] = s->sprite[2] = getSpriteIndex("SilverDoor");
 }
 
 void initGoldDoor(Entity *e)
 {
+	Structure *s;
+	
 	initDoor(e);
 	
-	STRNCPY(e->requiredKey, "Gold Key", MAX_NAME_LENGTH);
+	s = (Structure*)e;
+	
+	STRNCPY(s->requiredItem, "Gold Key", MAX_NAME_LENGTH);
 
-	e->speed = 2;
+	s->speed = 2;
 
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("GoldDoor");
+	s->sprite[0] = s->sprite[1] = e->sprite[2] = getSpriteIndex("GoldDoor");
 }
 
 static void tick(void)
 {
-	self->dx = self->dy = 0;
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	s->dx = s->dy = 0;
 
 	if (isOpening())
 	{
-		getSlope(self->tx, self->ty, self->x, self->y, &self->dx, &self->dy);
+		getSlope(s->tx, s->ty, s->x, s->y, &s->dx, &s->dy);
 
-		self->dx *= self->speed;
-		self->dy *= self->speed;
+		s->dx *= s->speed;
+		s->dy *= s->speed;
 
-		if (abs(self->x - self->tx) < self->speed && abs(self->y - self->ty) < self->speed)
+		if (abs(s->x - s->tx) < s->speed && abs(s->y - s->ty) < s->speed)
 		{
-			self->x = self->tx;
-			self->y = self->ty;
+			s->x = s->tx;
+			s->y = s->ty;
 		}
 
-		self->isStatic = 0;
+		s->isStatic = 0;
 	}
 	else if (isClosing())
 	{
-		getSlope(self->closedX, self->closedY, self->x, self->y, &self->dx, &self->dy);
+		getSlope(s->closedX, s->closedY, s->x, s->y, &s->dx, &s->dy);
 
-		self->dx *= self->speed;
-		self->dy *= self->speed;
+		s->dx *= s->speed;
+		s->dy *= s->speed;
 
-		if (abs(self->x - self->closedX) < self->speed && abs(self->y - self->closedY) < self->speed)
+		if (abs(s->x - s->closedX) < s->speed && abs(self->y - s->closedY) < s->speed)
 		{
-			self->x = self->closedX;
-			self->y = self->closedY;
+			s->x = s->closedX;
+			s->y = s->closedY;
 		}
 
-		self->isStatic = 0;
+		s->isStatic = 0;
 	}
 
-	if (self->dx == 0 && self->dy == 0 && !self->isStatic)
+	if (s->dx == 0 && s->dy == 0 && !s->isStatic)
 	{
-		self->isStatic = 1;
+		s->isStatic = 1;
 
 		playSound(SND_DOOR_FINISH, CH_MECHANICAL);
 	}
@@ -133,27 +153,31 @@ static void tick(void)
 
 static void touch(Entity *other)
 {
-	if ((other->type != ET_BOB && self->isLocked) || (other->type != ET_BOB && other->type != ET_ENEMY))
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if ((other->type != ET_BOB && s->isLocked) || (other->type != ET_BOB && other->type != ET_ENEMY))
 	{
 		return;
 	}
 
-	if (self->isLocked && !dev.cheatKeys)
+	if (s->isLocked && !dev.cheatKeys)
 	{
 		if (isClosed())
 		{
-			if (strlen(self->requiredKey) != 0)
+			if (strlen(s->requiredItem) != 0)
 			{
 				openWithKey();
 			}
-			else if (self->thinkTime == 0)
+			else if (s->thinkTime == 0)
 			{
 				setGameplayMessage(MSG_GAMEPLAY, "Door is locked");
 
 				playSound(SND_DENIED, CH_MECHANICAL);
 			}
 
-			self->thinkTime = 2;
+			s->thinkTime = 2;
 
 			return;
 		}
@@ -163,56 +187,66 @@ static void touch(Entity *other)
 		}
 	}
 
-	if (self->state != DOOR_OPEN)
+	if (s->state != DOOR_OPEN)
 	{
 		playSound(SND_DOOR_START, CH_MECHANICAL);
 	}
 
-	self->state = DOOR_OPEN;
+	s->state = DOOR_OPEN;
 }
 
 static void openWithKey(void)
 {
-	if (hasItem(self->requiredKey))
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (hasItem(s->requiredItem))
 	{
-		if (self->thinkTime <= 0)
+		if (s->thinkTime <= 0)
 		{
-			setGameplayMessage(MSG_GAMEPLAY, "%s required", self->requiredKey);
+			setGameplayMessage(MSG_GAMEPLAY, "%s required", s->requiredItem);
 
 			playSound(SND_DENIED, CH_MECHANICAL);
 		}
 
-		self->thinkTime = 2;
+		s->thinkTime = 2;
 
 		return;
 	}
 
-	removeItem(self->requiredKey);
+	removeItem(s->requiredItem);
 
-	setGameplayMessage(MSG_GAMEPLAY, "%s removed", self->requiredKey);
+	setGameplayMessage(MSG_GAMEPLAY, "%s removed", s->requiredItem);
 
-	STRNCPY(self->requiredKey, "", MAX_NAME_LENGTH);
-	self->isLocked = 0;
+	STRNCPY(s->requiredItem, "", MAX_NAME_LENGTH);
+	s->isLocked = 0;
 
-	if (self->state != DOOR_OPEN)
+	if (s->state != DOOR_OPEN)
 	{
 		playSound(SND_DOOR_START, CH_MECHANICAL);
 	}
 
-	self->state = DOOR_OPEN;
+	s->state = DOOR_OPEN;
 }
 
 static int isOpening(void)
 {
-	return (self->state == DOOR_OPEN && ((int) self->x != (int) self->tx || (int) self->y != (int) self->ty));
+	Structure *s = (Structure*)self;
+	
+	return (s->state == DOOR_OPEN && ((int) s->x != (int) s->tx || (int) s->y != (int) s->ty));
 }
 
 static int isClosing(void)
 {
-	return (self->state == DOOR_CLOSED && ((int) self->x != self->closedX || (int) self->y != self->closedY));
+	Structure *s = (Structure*)self;
+	
+	return (s->state == DOOR_CLOSED && ((int) s->x != s->closedX || (int) s->y != s->closedY));
 }
 
 static int isClosed(void)
 {
-	return (self->state == DOOR_CLOSED && ((int) self->x == self->closedX && (int) self->y == self->closedY));
+	Structure *s = (Structure*)self;
+	
+	return (s->state == DOOR_CLOSED && ((int) s->x == s->closedX && (int) s->y == s->closedY));
 }
diff --git a/src/world/entities/structures/exit.c b/src/world/entities/structures/exit.c
index ceb4f8d..016ce22 100644
--- a/src/world/entities/structures/exit.c
+++ b/src/world/entities/structures/exit.c
@@ -23,75 +23,92 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 static void tick(void);
 static void action(void);
 static void touch(Entity *other);
-static SDL_Rect getBounds(void);
+static SDL_Rect *getBounds(void);
 
 void initExit(Entity *e)
 {
-	e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex("Exit");
-
-	e->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS;
-
-	e->isStatic = 1;
-
-	e->active = 0;
+	Structure *s;
 	
-	if (!e->active)
+	initEntity(e);
+	
+	s = (Structure*)e;
+	
+	s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("Exit");
+
+	s->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS;
+
+	s->isStatic = 1;
+
+	s->active = 0;
+	
+	if (!s->active)
 	{
-		e->spriteFrame = 0;
+		s->spriteFrame = 0;
 	}
 	else
 	{
-		e->spriteFrame = 1;
+		s->spriteFrame = 1;
 	}
 
-	e->spriteTime = -1;
+	s->spriteTime = -1;
 	
-	e->tick = tick;
-	e->action = action;
-	e->touch = touch;
-	e->getBounds = getBounds;
+	s->tick = tick;
+	s->action = action;
+	s->touch = touch;
+	s->getBounds = getBounds;
 }
 
 static void tick(void)
 {
-	if (!self->active)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (!s->active)
 	{
-		self->bobTouching = MAX(self->bobTouching - 1, 0);
+		s->bobTouching = MAX(s->bobTouching - 1, 0);
 	}
 }
 
 static void action(void)
 {
 	Objective *o;
+	Structure *s;
 	
-	if (!self->active)
+	s = (Structure*)self;
+	
+	if (!s->active)
 	{
-		self->active = 1;
+		s->active = 1;
 
 		for (o = world.objectiveHead.next ; o != NULL ; o = o->next)
 		{
 			if (o->required && strcmp(o->targetName, "EXIT") != 0 && o->currentValue < o->targetValue)
 			{
-				self->active = 0;
+				s->active = 0;
 			}
 		}
 
-		if (self->active)
+		if (s->active)
 		{
-			self->spriteFrame = 1;
+			s->spriteFrame = 1;
 		}
 	}
 
-	self->thinkTime = FPS;
+	s->thinkTime = FPS;
 }
 
 static void touch(Entity *other)
 {
+	Structure *s;
+	
+	s = (Structure*)self;
+	
 	if (other->type == ET_BOB && !world.isReturnVisit)
 	{
-		if (self->bobTouching == 0)
+		if (s->bobTouching == 0)
 		{
-			if (self->active)
+			if (s->active)
 			{
 				updateObjective("EXIT");
 				world.missionCompleteTimer = (int) (FPS * 1.5);
@@ -105,16 +122,16 @@ static void touch(Entity *other)
 			}
 		}
 
-		self->bobTouching = 2;
+		s->bobTouching = 2;
 	}
 }
 
-static SDL_Rect getBounds(void)
+static SDL_Rect *getBounds(void)
 {
 	self->bounds.x = self->x + 64;
 	self->bounds.y = self->y;
 	self->bounds.w = 2;
 	self->bounds.h = self->h;
 
-	return self->bounds;
+	return &self->bounds;
 }
diff --git a/src/world/entities/structures/exit.h b/src/world/entities/structures/exit.h
index d751027..a1ec12f 100644
--- a/src/world/entities/structures/exit.h
+++ b/src/world/entities/structures/exit.h
@@ -24,6 +24,7 @@ extern int getSpriteIndex(char *name);
 extern void updateObjective(char *targetName);
 extern void setGameplayMessage(int type, char *format, ...);
 extern void stopMusic(void);
+extern void initEntity(Entity *e);
 
 extern Entity *self;
 extern World world;
diff --git a/src/world/entities/structures/horizontalDoor.c b/src/world/entities/structures/horizontalDoor.c
index 57a2f21..76cf1fb 100644
--- a/src/world/entities/structures/horizontalDoor.c
+++ b/src/world/entities/structures/horizontalDoor.c
@@ -31,19 +31,19 @@ void initBronzeHorizontalDoor(Entity *e)
 {
 	initHorizontalDoor(e);
 	
-	STRNCPY(e->requiredKey, "Bronze Key", MAX_NAME_LENGTH);
+	STRNCPY(((Structure*)e)->requiredItem, "Bronze Key", MAX_NAME_LENGTH);
 }
 
 void initSilverHorizontalDoor(Entity *e)
 {
 	initHorizontalDoor(e);
 	
-	STRNCPY(e->requiredKey, "Silver Key", MAX_NAME_LENGTH);
+	STRNCPY(((Structure*)e)->requiredItem, "Silver Key", MAX_NAME_LENGTH);
 }
 
 void initGoldHorizontalDoor(Entity *e)
 {
 	initHorizontalDoor(e);
 	
-	STRNCPY(e->requiredKey, "Gold Key", MAX_NAME_LENGTH);
+	STRNCPY(((Structure*)e)->requiredItem, "Gold Key", MAX_NAME_LENGTH);
 }
diff --git a/src/world/entities/structures/itemPad.c b/src/world/entities/structures/itemPad.c
index d64598b..733193f 100644
--- a/src/world/entities/structures/itemPad.c
+++ b/src/world/entities/structures/itemPad.c
@@ -48,16 +48,23 @@ void initItemPad(Entity *e)
 
 static void tick(void)
 {
-	self->bobTouching = MAX(self->bobTouching - 1, 0);
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	s->bobTouching = MAX(s->bobTouching - 1, 0);
 }
 
 static void touch(Entity *other)
 {
-	Entity *i;
+	Structure *s;
+	Item *i;
 	
-	if (other->type == ET_BOB && !self->active)
+	s = (Structure*)self;
+	
+	if (other->type == ET_BOB && !s->active)
 	{
-		i = getItem(self->requiredItem);
+		i = getItem(s->requiredItem);
 
 		if (i != NULL)
 		{
@@ -65,26 +72,26 @@ static void touch(Entity *other)
 			
 			i->flags &= ~EF_GONE;
 			
-			i->x = self->x + (self->w / 2) - (i->w / 2);
-			i->y = self->y - i->h;
+			i->x = s->x + (s->w / 2) - (i->w / 2);
+			i->y = s->y - i->h;
 			
 			i->canBeCarried = i->canBePickedUp = i->isMissionTarget = 0;
 			
-			self->active = 1;
+			s->active = 1;
 
-			setGameplayMessage(MSG_GAMEPLAY, "%s removed", self->requiredItem);
+			setGameplayMessage(MSG_GAMEPLAY, "%s removed", s->requiredItem);
 
-			self->sprite[FACING_LEFT] = self->sprite[FACING_RIGHT] = self->sprite[FACING_DIE] = getSpriteIndex("ItemPadActive");
+			s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("ItemPadActive");
 
-			self->spriteFrame = 0;
+			s->spriteFrame = 0;
 
-			updateObjective(self->name);
+			updateObjective(s->name);
 		}
-		else if (!self->bobTouching)
+		else if (!s->bobTouching)
 		{
-			setGameplayMessage(MSG_GAMEPLAY, "%s required", self->requiredItem);
+			setGameplayMessage(MSG_GAMEPLAY, "%s required", s->requiredItem);
 		}
 
-		self->bobTouching = 2;
+		s->bobTouching = 2;
 	}
 }
diff --git a/src/world/entities/structures/itemPad.h b/src/world/entities/structures/itemPad.h
index 9299e97..67381db 100644
--- a/src/world/entities/structures/itemPad.h
+++ b/src/world/entities/structures/itemPad.h
@@ -25,6 +25,6 @@ extern int getSpriteIndex(char *name);
 extern void updateObjective(char *targetName);
 extern void setGameplayMessage(int type, char *format, ...);
 extern void removeItem(char *name);
-extern Entity *getItem(char *name);
+extern Item *getItem(char *name);
 
 extern Entity *self;
diff --git a/src/world/entities/structures/lift.c b/src/world/entities/structures/lift.c
index dbb0ad8..42561d1 100644
--- a/src/world/entities/structures/lift.c
+++ b/src/world/entities/structures/lift.c
@@ -25,62 +25,70 @@ static void activate(int active);
 
 void initLift(Entity *e)
 {
+	Structure *s;
+	
 	initEntity(e);
 	
-	e->state = LIFT_GOTO_FINISH;
-
-	e->flags |= EF_WEIGHTLESS | EF_NO_ENVIRONMENT | EF_EXPLODES | EF_NO_CLIP | EF_ALWAYS_PROCESS | EF_NO_TELEPORT;
-
-	e->speed = 2;
-
-	e->waitTime = 2;
-
-	e->startX = e->startY = -1;
-
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("Lift");
-
-	e->active = 1;
+	s = (Structure*)e;
 	
-	e->action = action;
-	e->activate = activate;
+	s->state = LIFT_GOTO_FINISH;
+
+	s->flags |= EF_WEIGHTLESS | EF_NO_ENVIRONMENT | EF_EXPLODES | EF_NO_CLIP | EF_ALWAYS_PROCESS | EF_NO_TELEPORT;
+
+	s->speed = 2;
+
+	s->waitTime = 2;
+
+	s->startX = s->startY = -1;
+
+	s->sprite[0] = s->sprite[1] = s->sprite[2] = getSpriteIndex("Lift");
+
+	s->active = 1;
+	
+	s->action = action;
+	s->activate = activate;
 }
 
 static void action(void)
 {
-	self->dx = self->dy = 0;
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	s->dx = s->dy = 0;
 
-	if (self->active)
+	if (s->active)
 	{
-		if (self->state == LIFT_GOTO_START)
+		if (s->state == LIFT_GOTO_START)
 		{
-			getSlope(self->startX, self->startY, self->x, self->y, &self->dx, &self->dy);
+			getSlope(s->startX, s->startY, s->x, s->y, &s->dx, &s->dy);
 
-			self->dx *= self->speed;
-			self->dy *= self->speed;
+			s->dx *= s->speed;
+			s->dy *= s->speed;
 
-			if (abs(self->x - self->startX) < self->speed && abs(self->y - self->startY) < self->speed)
+			if (abs(s->x - s->startX) < s->speed && abs(s->y - s->startY) < s->speed)
 			{
-				self->x = self->startX;
-				self->y = self->startY;
-				self->state = LIFT_GOTO_FINISH;
-				self->thinkTime = self->waitTime * FPS;
-				self->dx = self->dy = 0;
+				s->x = s->startX;
+				s->y = s->startY;
+				s->state = LIFT_GOTO_FINISH;
+				s->thinkTime = s->waitTime * FPS;
+				s->dx = s->dy = 0;
 			}
 		}
-		else if (self->state == LIFT_GOTO_FINISH)
+		else if (s->state == LIFT_GOTO_FINISH)
 		{
-			getSlope(self->tx, self->ty, self->x, self->y, &self->dx, &self->dy);
+			getSlope(s->tx, s->ty, s->x, s->y, &s->dx, &s->dy);
 
-			self->dx *= self->speed;
-			self->dy *= self->speed;
+			s->dx *= s->speed;
+			s->dy *= s->speed;
 
-			if (abs(self->x - self->tx) < self->speed && abs(self->y - self->ty) < self->speed)
+			if (abs(s->x - s->tx) < s->speed && abs(s->y - s->ty) < s->speed)
 			{
-				self->x = self->tx;
-				self->y = self->ty;
-				self->state = LIFT_GOTO_START;
-				self->thinkTime = self->waitTime * FPS;
-				self->dx = self->dy = 0;
+				s->x = s->tx;
+				s->y = s->ty;
+				s->state = LIFT_GOTO_START;
+				s->thinkTime = s->waitTime * FPS;
+				s->dx = s->dy = 0;
 			}
 		}
 	}
diff --git a/src/world/entities/structures/powerPoint.c b/src/world/entities/structures/powerPoint.c
index a71839e..f70fbe7 100644
--- a/src/world/entities/structures/powerPoint.c
+++ b/src/world/entities/structures/powerPoint.c
@@ -26,72 +26,88 @@ static void touch(Entity *other);
 
 void initPowerPoint(Entity *e)
 {
-	initEntity(e);
-
-	e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex("PowerPoint");
-
-	e->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS;
-
-	e->requiredPower = 100;
-
-	e->isStatic = 1;
+	Structure *s;
 	
-	e->tick = tick;
-	e->action = action;
-	e->touch = touch;
+	initEntity(e);
+	
+	s = (Structure*)e;
+
+	s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("PowerPoint");
+
+	s->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS;
+
+	s->requiredPower = 100;
+
+	s->isStatic = 1;
+	
+	s->tick = tick;
+	s->action = action;
+	s->touch = touch;
 }
 
 static void tick(void)
 {
-	if (!self->active)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (!s->active)
 	{
-		self->bobTouching = MAX(self->bobTouching - 1, 0);
+		s->bobTouching = MAX(s->bobTouching - 1, 0);
 
-		if (self->bobTouching == 0)
+		if (s->bobTouching == 0)
 		{
-			self->spriteFrame = 0;
-			self->spriteTime = -1;
-			self->thinkTime = FPS / 2;
+			s->spriteFrame = 0;
+			s->spriteTime = -1;
+			s->thinkTime = FPS / 2;
 		}
 	}
 }
 
 static void action(void)
 {
-	self->spriteFrame = MIN(self->spriteFrame + 1, 3);
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	s->spriteFrame = MIN(s->spriteFrame + 1, 3);
 
-	if (!self->active && self->spriteFrame == 3)
+	if (!s->active && s->spriteFrame == 3)
 	{
-		activateEntities(self->targetNames, 1);
+		activateEntities(s->targetNames, 1);
 		
-		setGameplayMessage(MSG_GAMEPLAY, self->message);
+		setGameplayMessage(MSG_GAMEPLAY, s->message);
 		
 		if (!dev.cheatPower)
 		{
-			world.bob->power -= self->requiredPower;
+			world.bob->power -= s->requiredPower;
 		}
 		
-		self->requiredPower = 0;
+		s->requiredPower = 0;
 		
-		self->active = 1;
+		s->active = 1;
 	}
 	else
 	{
-		self->thinkTime = FPS / 2;
+		s->thinkTime = FPS / 2;
 	}
 }
 
 static void touch(Entity *other)
 {
-	if (!self->active && other->type == ET_BOB && other->dx == 0)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (!s->active && other->type == ET_BOB && other->dx == 0)
 	{
-		if (world.bob->power < self->requiredPower && self->bobTouching == 0 && !dev.cheatPower)
+		if (world.bob->power < s->requiredPower && s->bobTouching == 0 && !dev.cheatPower)
 		{
-			setGameplayMessage(MSG_GAMEPLAY, "Not enough power (%d units required)", self->requiredPower);
+			setGameplayMessage(MSG_GAMEPLAY, "Not enough power (%d units required)", s->requiredPower);
 		}
 		else
 		{
-			self->bobTouching = 2;
+			s->bobTouching = 2;
 		}
 	}
 }
diff --git a/src/world/entities/structures/powerPool.c b/src/world/entities/structures/powerPool.c
index 903cea1..7ac8621 100644
--- a/src/world/entities/structures/powerPool.c
+++ b/src/world/entities/structures/powerPool.c
@@ -26,57 +26,75 @@ static void touch(Entity *other);
 
 void initPowerPool(Entity *e)
 {
-	e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex("PowerPool");
-
-	e->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_IGNORE_BULLETS;
-
-	e->plane = PLANE_FOREGROUND;
-
-	e->isStatic = 1;
+	Structure *s;
 	
-	e->tick = tick;
-	e->action = action;
-	e->touch = touch;
+	initEntity(e);
+	
+	s = (Structure*)e;
+	
+	s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("PowerPool");
+
+	s->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_IGNORE_BULLETS;
+
+	s->plane = PLANE_FOREGROUND;
+
+	s->isStatic = 1;
+	
+	s->tick = tick;
+	s->action = action;
+	s->touch = touch;
 }
 
 static void tick(void)
 {
-	if (self->active)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (s->active)
 	{
-		self->spriteTime--;
-		if (self->spriteTime <= 0)
+		s->spriteTime--;
+		if (s->spriteTime <= 0)
 		{
-			self->spriteFrame = (int) (1 + (rand() % 6));
-			self->spriteTime = 12;
+			s->spriteFrame = (int) (1 + (rand() % 6));
+			s->spriteTime = 12;
 		}
 	}
 }
 
 static void action(void)
 {
-	self->active = 1;
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	s->active = 1;
 
-	if (self->spriteFrame == 0)
+	if (s->spriteFrame == 0)
 	{
-		self->spriteFrame = (int) (1 + (rand() % 6));
-		self->spriteTime = 12;
+		s->spriteFrame = (int) (1 + (rand() % 6));
+		s->spriteTime = 12;
 	}
 
-	self->thinkTime = FPS * 99999;
+	s->thinkTime = FPS * 99999;
 }
 
 static void touch(Entity *other)
 {
-	if (self->active && other->type == ET_BOB && world.bob->power < world.bob->powerMax)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (s->active && other->type == ET_BOB && world.bob->power < world.bob->powerMax)
 	{
 		world.bob->power = MIN(world.bob->power + 0.05, world.bob->powerMax);
 
 		if (world.bob->power == world.bob->powerMax)
 		{
-			self->thinkTime = FPS * 10;
-			self->spriteTime = -1;
-			self->spriteFrame = 0;
-			self->active = 0;
+			s->thinkTime = FPS * 10;
+			s->spriteTime = -1;
+			s->spriteFrame = 0;
+			s->active = 0;
 		}
 	}
 }
diff --git a/src/world/entities/structures/powerPool.h b/src/world/entities/structures/powerPool.h
index 5ae19f7..9e325c5 100644
--- a/src/world/entities/structures/powerPool.h
+++ b/src/world/entities/structures/powerPool.h
@@ -21,6 +21,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #include "../../../common.h"
 
 extern int getSpriteIndex(char *name);
+extern void initEntity(Entity *e);
 
 extern Entity *self;
 extern World world;
diff --git a/src/world/entities/structures/pressurePlate.c b/src/world/entities/structures/pressurePlate.c
index 4a9054d..3cc9e68 100644
--- a/src/world/entities/structures/pressurePlate.c
+++ b/src/world/entities/structures/pressurePlate.c
@@ -25,49 +25,61 @@ static void touch(Entity *other);
 
 void initPressurePlate(Entity *e)
 {
+	Structure *s;
+	
 	initEntity(e);
 	
-	e->sprite[FACING_LEFT] = e->sprite[FACING_RIGHT] = e->sprite[FACING_DIE] = getSpriteIndex("PressurePlate");
-
-	e->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS;
-
-	e->plane = PLANE_FOREGROUND;
-
-	e->isStatic = 1;
+	s = (Structure*)e;
 	
-	e->tick = tick;
-	e->touch = touch;
+	s->sprite[FACING_LEFT] = s->sprite[FACING_RIGHT] = s->sprite[FACING_DIE] = getSpriteIndex("PressurePlate");
+
+	s->flags |= EF_WEIGHTLESS | EF_NO_CLIP | EF_NO_ENVIRONMENT | EF_IGNORE_BULLETS;
+
+	s->plane = PLANE_FOREGROUND;
+
+	s->isStatic = 1;
+	
+	s->tick = tick;
+	s->touch = touch;
 }
 
 static void tick(void)
 {
-	if (self->isWeighted)
+	Structure *s;
+	
+	s = (Structure*)self;
+	
+	if (s->isWeighted)
 	{
-		self->weightApplied = MAX(self->weightApplied - 1, 0);
+		s->weightApplied = MAX(s->weightApplied - 1, 0);
 
-		if (self->active && self->weightApplied == 0)
+		if (s->active && s->weightApplied == 0)
 		{
-			self->active = 0;
-			self->spriteFrame = 0;
+			s->active = 0;
+			s->spriteFrame = 0;
 
-			activateEntities(self->targetNames, 0);
+			activateEntities(s->targetNames, 0);
 		}
 	}
 }
 
 static void touch(Entity *other)
 {
+	Structure *s;
+	
+	s = (Structure*)self;
+	
 	if (other->type == ET_BOB || other->type == ET_PUSHBLOCK)
 	{
-		if (!self->active)
+		if (!s->active)
 		{
-			activateEntities(self->targetNames, 1);
+			activateEntities(s->targetNames, 1);
 
 			playSound(SND_PRESSURE_PLATE, CH_MECHANICAL);
 		}
 
-		self->active = 1;
-		self->spriteFrame = 1;
-		self->weightApplied = 5;
+		s->active = 1;
+		s->spriteFrame = 1;
+		s->weightApplied = 5;
 	}
 }
diff --git a/src/world/entities/structures/pushBlock.c b/src/world/entities/structures/pushBlock.c
index 2517410..f5ae40b 100644
--- a/src/world/entities/structures/pushBlock.c
+++ b/src/world/entities/structures/pushBlock.c
@@ -24,25 +24,33 @@ static void activate(int active);
 
 void initPushBlock(Entity *e)
 {
+	Structure *s;
+	
 	initEntity(e);
 	
-	e->isSolid = 1;
-
-	e->startX = e->startY = -1;
-
-	e->flags |= EF_EXPLODES | EF_ALWAYS_PROCESS;
+	s = (Structure*)e;
 	
-	e->activate = activate;
+	s->isSolid = 1;
+
+	s->startX = s->startY = -1;
+
+	s->flags |= EF_EXPLODES | EF_ALWAYS_PROCESS;
+	
+	s->activate = activate;
 }
 
 static void activate(int active)
 {
+	Structure *s;
+	
+	s = (Structure*)self;
+	
 	if (self->active)
 	{
 		addTeleportStars(self);
-		self->x = self->startX;
-		self->y = self->startY;
-		self->dx = self->dy = 0;
+		s->x = s->startX;
+		s->y = s->startY;
+		s->dx = s->dy = 0;
 		addTeleportStars(self);
 		playSound(SND_APPEAR, CH_ANY);
 	}
diff --git a/src/world/entities/traps/laserTrap.c b/src/world/entities/traps/laserTrap.c
index 3b0e42a..17789e0 100644
--- a/src/world/entities/traps/laserTrap.c
+++ b/src/world/entities/traps/laserTrap.c
@@ -28,22 +28,26 @@ static void activate(int active);
 
 void initLaserTrap(Entity *e)
 {
+	Trap *t;
+	
 	initEntity(e);
 	
-	e->flags |= EF_WEIGHTLESS | EF_IGNORE_BULLETS | EF_NO_ENVIRONMENT | EF_NO_CLIP | EF_ALWAYS_PROCESS;
-
-	e->onTime = FPS * 2;
-	e->offTime = FPS * 2;
-
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = getSpriteIndex("LaserTrap");
-
-	e->active = 1;
+	t = (Trap*)e;
 	
-	e->init = init;
-	e->tick = tick;
-	e->action = action;
-	e->touch = touch;
-	e->activate = activate;
+	t->flags |= EF_WEIGHTLESS | EF_IGNORE_BULLETS | EF_NO_ENVIRONMENT | EF_NO_CLIP | EF_ALWAYS_PROCESS;
+
+	t->onTime = FPS * 2;
+	t->offTime = FPS * 2;
+
+	t->sprite[0] = t->sprite[1] = t->sprite[2] = getSpriteIndex("LaserTrap");
+
+	t->active = 1;
+	
+	t->init = init;
+	t->tick = tick;
+	t->action = action;
+	t->touch = touch;
+	t->activate = activate;
 }
 
 static void init(void)
@@ -56,40 +60,52 @@ static void init(void)
 
 static void tick(void)
 {
-	if (!self->active && self->spriteTime == -1)
+	Trap *t;
+	
+	t = (Trap*)self;
+	
+	if (!t->active && t->spriteTime == -1)
 	{
-		self->flags |= EF_GONE;
+		t->flags |= EF_GONE;
 	}
 }
 
 static void action(void)
 {
-	if (self->offTime != 0)
+	Trap *t;
+	
+	t = (Trap*)self;
+	
+	if (t->offTime != 0)
 	{
-		if (!self->active)
+		if (!t->active)
 		{
-			self->thinkTime = self->onTime;
-			self->spriteFrame = 0;
-			self->spriteTime = 0;
-			self->flags &= ~EF_GONE;
+			t->thinkTime = t->onTime;
+			t->spriteFrame = 0;
+			t->spriteTime = 0;
+			t->flags &= ~EF_GONE;
 		}
-		else if (self->offTime > 0)
+		else if (t->offTime > 0)
 		{
-			self->thinkTime = self->offTime;
-			self->spriteTime = 0;
+			t->thinkTime = t->offTime;
+			t->spriteTime = 0;
 		}
 
-		self->active = !self->active;
+		t->active = !t->active;
 	}
 	else
 	{
-		self->spriteTime = -1;
-		self->spriteFrame = 4;
+		t->spriteTime = -1;
+		t->spriteFrame = 4;
 	}
 }
 
 static void touch(Entity *other)
 {
+	Trap *t;
+	
+	t = (Trap*)self;
+	
 	if (other != NULL && (other->type == ET_BOB || other->type == ET_ENEMY))
 	{
 		if (!(other->flags & EF_IMMUNE))
@@ -99,7 +115,7 @@ static void touch(Entity *other)
 				other->dx = rrnd(-12, 12);
 				other->dy = rrnd(-8, 0);
 
-				if (self->offTime != 0)
+				if (t->offTime != 0)
 				{
 					other->applyDamage((int) (other->healthMax / 4));
 				}
@@ -110,7 +126,7 @@ static void touch(Entity *other)
 				}
 			}
 
-			if (other == world.bob && world.bob->stunTimer == 0)
+			if (other == (Entity*)world.bob && world.bob->stunTimer == 0)
 			{
 				stunPlayer();
 			}
@@ -118,11 +134,11 @@ static void touch(Entity *other)
 
 		if (other->flags & EF_EXPLODES)
 		{
-			addSparkParticles(self->x, self->y);
+			addSparkParticles(t->x, t->y);
 		}
 		else
 		{
-			addSmallFleshChunk(self->x, self->y);
+			addSmallFleshChunk(t->x, t->y);
 		}
 	}
 }
diff --git a/src/world/entities/unit.c b/src/world/entities/unit.c
index 7fe99bb..d2f4a3e 100644
--- a/src/world/entities/unit.c
+++ b/src/world/entities/unit.c
@@ -22,120 +22,121 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 void unitTick(void);
 static void attack(void);
+static int canFire(Entity *target);
 
 void initUnit(Entity *e)
 {
+	Unit *u;
+	
 	initEntity(e);
 	
-	e->oxygen = MAX_OXYGEN;
+	u = (Unit*)e;
+	
+	u->oxygen = MAX_OXYGEN;
 
-	e->canCarryItem = rand() % 100 < 85;
+	u->canCarryItem = rand() % 100 < 85;
 
 	if (world.isOutpostMission)
 	{
-		e->canCarryItem = 1;
-		e->health = e->healthMax = rrnd(1, 4);
+		u->canCarryItem = 1;
+		u->health = u->healthMax = rrnd(1, 4);
 	}
 
-	e->spriteFrame = 0;
+	u->spriteFrame = 0;
 
-	e->startX = e->startY = -1;
+	u->startX = u->startY = -1;
 
-	e->tick = unitTick;
-	e->action = lookForPlayer;
-	e->attack = attack;
+	u->tick = unitTick;
+	u->action = lookForPlayer;
+	u->attack = attack;
+	u->canFire = canFire;
 }
 
 void reInitUnit(Entity *e)
 {
-	if (e->startX == -1 && e->startY == -1)
+	Unit *u;
+	
+	u = (Unit*)self;
+	
+	if (u->startX == -1 && u->startY == -1)
 	{
-		e->startX = (int) e->x;
-		e->startY = (int) e->y;
+		u->startX = (int) u->x;
+		u->startY = (int) u->y;
 	}
 
-	if (e->isMissionTarget)
+	if (u->isMissionTarget)
 	{
-		e->flags |= EF_BOMB_SHIELD;
+		u->flags |= EF_BOMB_SHIELD;
 	}
 }
 
 void unitTick(void)
 {
-	if (self->alive == ALIVE_ALIVE)
+	Unit *u;
+	
+	u = (Unit*)self;
+	
+	if (u->alive == ALIVE_ALIVE)
 	{
-		self->reload = limit(self->reload - 1, 0, FPS);
+		u->reload = limit(u->reload - 1, 0, FPS);
 	}
 
-	switch (self->environment)
+	switch (u->environment)
 	{
 		case ENV_AIR:
-			self->oxygen = limit(self->oxygen + 4, 0, MAX_OXYGEN);
+			u->oxygen = limit(u->oxygen + 4, 0, MAX_OXYGEN);
 			break;
 
 		case ENV_WATER:
-			self->oxygen = limit(self->oxygen - 1, 0, MAX_OXYGEN);
-			if (self->oxygen == 0 && world.frameCounter % 30 == 0)
+			u->oxygen = limit(u->oxygen - 1, 0, MAX_OXYGEN);
+			if (u->oxygen == 0 && world.frameCounter % 30 == 0)
 			{
-				self->health--;
+				u->health--;
 			}
 			break;
 
 		case ENV_SLIME:
 		case ENV_LAVA:
-			if (self->alive == ALIVE_ALIVE)
+			if (u->alive == ALIVE_ALIVE)
 			{
-				self->health = 0;
+				u->health = 0;
 			}
 			break;
 	}
 
-	if (self->flags & EF_WATER_BREATHING)
+	if (u->flags & EF_WATER_BREATHING)
 	{
-		self->oxygen = MAX_OXYGEN;
+		u->oxygen = MAX_OXYGEN;
 	}
 
-	if (self->spawnedIn)
+	if (u->spawnedIn)
 	{
-		if (getDistance(self->x, self->y, world.bob->x, world.bob->y) < 1000)
+		if (getDistance(u->x, u->y, world.bob->x, world.bob->y) < 1000)
 		{
-			self->spawnedInTimer = FPS * 5;
+			u->spawnedInTimer = FPS * 5;
 		}
 
-		self->spawnedInTimer--;
-		if (self->spawnedInTimer <= 0)
+		u->spawnedInTimer--;
+		if (u->spawnedInTimer <= 0)
 		{
-			self->alive = ALIVE_DEAD;
+			u->alive = ALIVE_DEAD;
 		}
 	}
 }
 
-void dropCarriedItem(Entity *e)
-{
-	if (e->carriedItem != NULL)
-	{
-		e->carriedItem->x = (e->x + e->w / 2) - e->carriedItem->w / 2;
-		e->carriedItem->y = e->y;
-
-		e->carriedItem->dx = e->carriedItem->dy = 0;
-
-		world.entityTail->next = e->carriedItem;
-		world.entityTail = e->carriedItem;
-		world.entityTail->next = NULL;
-
-		e->carriedItem = NULL;
-	}
-}
-
 void unitReappear(void)
 {
 }
 
 static void attack(void)
 {
-	if (canFire(world.bob))
+	Unit *u;
+	
+	u = (Unit*)self;
+	
+	if (u->canFire((Entity*)world.bob))
 	{
-		switch (self->weaponType)
+		switch (u->weaponType)
 		{
 			case WPN_AIMED_PISTOL:
 				fireAimedShot(self);
@@ -170,10 +171,13 @@ static void attack(void)
 				break;
 
 			default:
-				printf("Can't fire weapon: %d\n", self->weaponType);
+				printf("Can't fire weapon: %d\n", u->weaponType);
 				break;
 		}
 	}
 }
 
-
+static int canFire(Entity *target)
+{
+	return 0;
+}
diff --git a/src/world/entities/unit.h b/src/world/entities/unit.h
index b07b958..5969d1d 100644
--- a/src/world/entities/unit.h
+++ b/src/world/entities/unit.h
@@ -25,7 +25,6 @@ extern void lookForPlayer(void);
 extern int rrnd(int low, int high);
 extern float limit(float i, float a, float b);
 extern int getDistance(int x1, int y1, int x2, int y2);
-extern int canFire(Entity *target);
 extern void fireAimedShot(Entity *e);
 extern void fireMachineGun(Entity *e);
 extern void fireGrenade(Entity *e);
diff --git a/src/world/items.c b/src/world/items.c
index 55c0de6..8294952 100644
--- a/src/world/items.c
+++ b/src/world/items.c
@@ -20,7 +20,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include "items.h"
 
-static void throwItem(Entity *e);
+static void throwItem(Item *i);
 static int getRandomPlayerWeaponAt(int x, int y);
 
 static int wpnIconSprite;
@@ -39,13 +39,13 @@ void initItems(void)
 
 void addRandomWeapon(double x, double y)
 {
-	Entity *wpn;
+	Item *wpn;
 	int type;
 	
-	wpn = malloc(sizeof(Entity));
-	memset(wpn, 0, sizeof(Entity));
-	world.entityTail->next = wpn;
-	world.entityTail = wpn;
+	wpn = malloc(sizeof(Item));
+	memset(wpn, 0, sizeof(Item));
+	world.entityTail->next = (Entity*)wpn;
+	world.entityTail = (Entity*)wpn;
 	
 	wpn->x = x;
 	wpn->y = y;
@@ -89,82 +89,82 @@ static int getRandomPlayerWeaponAt(int x, int y)
 
 void dropRandomCherry(double x, double y)
 {
-	Entity *e;
+	Item *i;
 	double r;
 
-	e = malloc(sizeof(Entity));
-	memset(e, 0, sizeof(Entity));
-	world.entityTail->next = e;
-	world.entityTail = e;
+	i = malloc(sizeof(Item));
+	memset(i, 0, sizeof(Item));
+	world.entityTail->next = (Entity*)i;
+	world.entityTail = (Entity*)i;
 	
 	r = rand() % 100;
 
 	if (r < 1)
 	{
-		STRNCPY(e->name, "bunch of cherries", MAX_NAME_LENGTH);
-		e->value = 10;
-		e->sprite[0] = e->sprite[1] = e->sprite[2] = cherrySprite[2];
+		STRNCPY(i->name, "bunch of cherries", MAX_NAME_LENGTH);
+		i->value = 10;
+		i->sprite[0] = i->sprite[1] = i->sprite[2] = cherrySprite[2];
 	}
 	else if (r < 10)
 	{
-		STRNCPY(e->name, "pair of cherries", MAX_NAME_LENGTH);
-		e->value = 3;
-		e->sprite[0] = e->sprite[1] = e->sprite[2] = cherrySprite[1];
+		STRNCPY(i->name, "pair of cherries", MAX_NAME_LENGTH);
+		i->value = 3;
+		i->sprite[0] = i->sprite[1] = i->sprite[2] = cherrySprite[1];
 	}
 	else
 	{
-		STRNCPY(e->name, "small cherry", MAX_NAME_LENGTH);
-		e->value = 1;
-		e->sprite[0] = e->sprite[1] = e->sprite[2] = cherrySprite[0];
+		STRNCPY(i->name, "small cherry", MAX_NAME_LENGTH);
+		i->value = 1;
+		i->sprite[0] = i->sprite[1] = i->sprite[2] = cherrySprite[0];
 	}
 
-	e->x = x;
-	e->y = y;
+	i->x = x;
+	i->y = y;
 
-	throwItem(e);
+	throwItem(i);
 }
 
 void dropBattery(double x, double y)
 {
-	Entity *e;
+	Item *i;
 	double r;
 
-	e = malloc(sizeof(Entity));
-	memset(e, 0, sizeof(Entity));
-	world.entityTail->next = e;
-	world.entityTail = e;
+	i = malloc(sizeof(Item));
+	memset(i, 0, sizeof(Item));
+	world.entityTail->next = (Entity*)i;
+	world.entityTail = (Entity*)i;
 
 	r = rand() % 100;
 
 	if (r < 1)
 	{
-		STRNCPY(e->name, "full battery", MAX_NAME_LENGTH);
-		e->value = 4;
+		STRNCPY(i->name, "full battery", MAX_NAME_LENGTH);
+		i->value = 4;
 	}
 	else if (r < 10)
 	{
-		STRNCPY(e->name, "battery", MAX_NAME_LENGTH);
-		e->value = 3;
+		STRNCPY(i->name, "battery", MAX_NAME_LENGTH);
+		i->value = 3;
 	}
 	else if (r < 25)
 	{
-		STRNCPY(e->name, "used battery", MAX_NAME_LENGTH);
-		e->value = 2;
+		STRNCPY(i->name, "used battery", MAX_NAME_LENGTH);
+		i->value = 2;
 	}
 	else
 	{
-		STRNCPY(e->name, "weak battery", MAX_NAME_LENGTH);
-		e->value = 1;
+		STRNCPY(i->name, "weak battery", MAX_NAME_LENGTH);
+		i->value = 1;
 	}
 
-	e->sprite[0] = e->sprite[1] = e->sprite[2] = batterySprite;
-	e->spriteTime = -1;
-	e->spriteFrame = e->value;
+	i->sprite[0] = i->sprite[1] = i->sprite[2] = batterySprite;
+	i->spriteTime = -1;
+	i->spriteFrame = i->value;
 	
-	e->x = x;
-	e->y = y;
+	i->x = x;
+	i->y = y;
 
-	throwItem(e);
+	throwItem(i);
 }
 
 void addRandomItems(double x, double y)
@@ -180,8 +180,8 @@ void addRandomItems(double x, double y)
 	}
 }
 
-static void throwItem(Entity *e)
+static void throwItem(Item *i)
 {
-	e->dx = rrnd(-3, 3);
-	e->dy = rrnd(-7, -5);
+	i->dx = rrnd(-3, 3);
+	i->dy = rrnd(-7, -5);
 }