diff --git a/README.md b/README.md
index 53617a7..51eaae7 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@ This is a rewrite of the [Blues Brothers](https://www.mobygames.com/game/blues-b
 
 ![Screenshot1](blues1.png) ![Screenshot2](bbja2.png)
 
-There is also early support for [Prehistorik 2](https://www.mobygames.com/game/prehistorik-2).
+There is also some support for [Prehistorik 2](https://www.mobygames.com/game/prehistorik-2).
 
 ## Requirements
 
diff --git a/p2/game.h b/p2/game.h
index 5c7279a..2108ba0 100644
--- a/p2/game.h
+++ b/p2/game.h
@@ -50,7 +50,7 @@ struct monster_t {
 struct thing_t {
 	void *ref;
 	int16_t counter;
-	int16_t unkE;
+	int16_t y_velocity;
 };
 
 struct object_t {
@@ -62,13 +62,13 @@ struct object_t {
 		struct player_t p; /* objects[1] */
 		struct club_projectile_t c; /* objects[2..5] */
 		struct monster_t m; /* objects[11..22] */
-		struct thing_t t;
+		struct thing_t t; /* objects[23..74] */
 	} data;
 	uint8_t hit_counter;
 };
 
 #define MONSTERS_COUNT 12
-#define OBJECTS_COUNT 108
+#define OBJECTS_COUNT 116
 /*
  offset count
       0     1 : club
@@ -78,9 +78,11 @@ struct object_t {
      11    12 : monsters
      23    32 : secret bonuses
      55    20 : items
-     75    16 : bonus scores
+     75    16 : scores
      91     7 : decor
      98     5 : boss level 5 (tree)
+    103     5 : boss projectiles
+    108     8 : boss energy bars
 */
 
 struct boss_level5_proj_t {
@@ -124,6 +126,11 @@ struct vars_t {
 	uint32_t score;
 	uint16_t score_extra_life;
 
+	uint16_t level_complete_secrets_count;
+	uint16_t level_complete_bonuses_count;
+	uint16_t level_current_secrets_count;
+	uint16_t level_current_bonuses_count;
+
 	uint8_t level_completed_flag;
 	uint8_t restart_level_flag;
 
@@ -133,7 +140,7 @@ struct vars_t {
 	uint16_t shake_screen_voffset;
 
 	uint8_t player_lifes;
-	uint8_t player_energy;
+	int8_t player_energy;
 	uint8_t player_death_flag;
 	uint8_t player_flying_flag;
 	uint8_t player_flying_counter;
@@ -206,28 +213,42 @@ struct vars_t {
 		uint8_t type0_hdir;
 	} monster;
 	struct {
-		int16_t x_pos, y_pos;
-		uint8_t hdir;
-		int16_t x_dist;
-	} boss;
+		uint16_t draw_counter;
+		uint8_t unk_counter;
+		int16_t x_velocity, y_velocity;
+		bool hdir; /* facing to the right */
+		int16_t x_dist; /* horizontal distance from player */
+		int16_t state_counter;
+		uint8_t anim_num;
+		const uint8_t *prev_anim;
+		const uint8_t *next_anim;
+		const uint8_t *current_anim;
+		struct {
+			int16_t x_pos, y_pos;
+			uint16_t spr_num;
+		} parts[5];
+		struct object_t *obj1;
+		struct object_t *obj2;
+		struct object_t *obj3;
+	} boss; /* gorilla */
 	struct {
 		uint8_t unk1;
 		uint8_t energy;
 		uint8_t state; /* 3: boss dead */
-		uint8_t unk4; /* spr103_pos */
-		uint8_t unk5; /* spr106_pos */
+		uint8_t spr103_pos;
+		uint8_t spr106_pos;
 		uint8_t unk6;
 		uint8_t counter;
 		uint8_t unk8;
 		struct boss_level5_proj_t proj_tbl[5];
 	} boss_level5; /* tree */
 	struct {
-		int16_t unk1;
-		uint8_t unk2;
-		uint8_t unk3;
+		uint16_t energy;
+		uint8_t seq_counter;
+		uint8_t hit_counter;
 		const uint8_t *seq;
 		const uint16_t *anim;
-	} boss_level9; /* minotaur statue */
+	} boss_level9; /* minotaur */
 	struct {
 		int16_t x_pos, y_pos;
 		uint16_t spr_num;
@@ -270,7 +291,9 @@ extern const uint8_t cos_tbl[256];
 extern const uint8_t sin_tbl[256];
 extern const uint16_t monster_spr_tbl[48];
 extern const uint8_t monster_anim_tbl[1100];
-extern const uint8_t boss_minotaur_seq_data[742];
+extern const uint8_t boss_minotaur_seq_data[86];
+extern const uint16_t boss_gorilla_data[19 * 10];
+extern const uint16_t boss_gorilla_spr_tbl[46 * 3]; /* uint16_t: spr1_num, uint16_t: spr2_num, uint8_t: dx, uint8_t: dy */
 
 /* game.c */
 extern void	update_input();
@@ -296,6 +319,8 @@ extern void	video_copy_img(const uint8_t *src);
 extern void	video_draw_panel(const uint8_t *src);
 extern void	video_draw_panel_number(int offset, int num);
 extern void	video_draw_number(int offset, int num);
+extern void	video_draw_character_spr(int offset, uint8_t chr);
+extern void	video_draw_string2(int offset, const char *str);
 extern void	video_draw_tile(const uint8_t *src, int x, int y);
 extern void	video_convert_tiles(uint8_t *data, int len);
 extern void	video_load_front_tiles();
diff --git a/p2/level.c b/p2/level.c
index 3eec898..280e695 100644
--- a/p2/level.c
+++ b/p2/level.c
@@ -156,6 +156,7 @@ static void load_level_data_fix_monsters_spr_num() {
 }
 
 static void load_level_data_init_secret_bonus_tiles() {
+	int count = 0;
 	for (int i = 0; i < MAX_LEVEL_BONUSES; ++i) {
 		struct level_bonus_t *bonus = &g_res.level.bonuses_tbl[i];
 		const uint16_t offset = bonus->pos;
@@ -163,8 +164,10 @@ static void load_level_data_init_secret_bonus_tiles() {
 			const uint8_t tile_num = level_get_tile(offset);
 			level_set_tile(offset, bonus->tile_num0);
 			bonus->tile_num1 = tile_num;
+			++count;
 		}
 	}
+	g_vars.level_complete_secrets_count = count;
 }
 
 static int compare_level_item_x_pos(const void *item1, const void *item2) {
@@ -217,7 +220,7 @@ static void load_level_data(int num) {
 	print_debug(DBG_GAME, "tilemap offset %d", offset);
 	load_leveldat(g_res.leveldat + offset, 0);
 	video_convert_tiles(g_res.leveldat + g_vars.tilemap.size + 512, offset - (g_vars.tilemap.size + 512));
-	print_debug(DBG_GAME, "start_pos %d,%d end_pos %d,%d", g_res.level.start_x_pos, g_res.level.start_y_pos, g_res.level.end_x_pos, g_res.level.end_y_pos);
+	print_debug(DBG_GAME, "start_pos %d,%d end_pos %d,%d", g_res.level.start_x_pos, g_res.level.start_y_pos, g_res.level.boss_x_pos, g_res.level.boss_y_pos);
 	load_level_data_init_animated_tiles();
 	load_level_data_init_transparent_tiles();
 	g_vars.snow.counter = 0;
@@ -238,8 +241,11 @@ static void load_level_data(int num) {
 			}
 		}
 	}
+	g_vars.level_complete_bonuses_count = count;
 	static const uint8_t type_tbl[] = { 0xFF, 0x0C, 0x0B, 0x0A, 0xFF, 0xFF, 0x00, 0xFF, 0xFF, 0x0E };
 	if (g_vars.level_num < 10 && type_tbl[g_vars.level_num] != 0xFF) {
+		g_vars.level_complete_bonuses_count *= 2;
+		g_vars.level_complete_secrets_count *= 2;
 	}
 }
 
@@ -890,6 +896,9 @@ static void level_update_tile1(uint16_t offset) {
 	case 1:
 		level_update_tile_type_1(offset);
 		break;
+	case 2:
+		level_update_tile_type_2(offset);
+		break;
 	default:
 		print_warning("Unhandled level_update_tile1 type %d", type);
 		break;
@@ -1024,7 +1033,8 @@ static void level_add_object23_bonus(int x_vel, int y_vel, int count) {
 			obj->x_pos = g_vars.current_bonus.x_pos;
 			obj->y_pos = g_vars.current_bonus.y_pos;
 			obj->x_velocity = x_vel;
-			obj->data.p.y_velocity = y_vel;
+			obj->data.t.y_velocity = y_vel;
+			obj->data.t.ref = 0;
 			x_vel = -x_vel;
 			++counter;
 			if ((counter & 1) == 0) {
@@ -1113,12 +1123,11 @@ static void level_monster_die(struct object_t *obj, struct level_monster_t *m, s
 	if ((m->flags & 1) == 0) {
 		g_vars.current_bonus.x_pos = obj->x_pos;
 		g_vars.current_bonus.y_pos = obj->y_pos;
-		g_vars.current_bonus.spr_num = 0x2046;
+		g_vars.current_bonus.spr_num = 0x2046; /* bones */
 		level_add_object23_bonus(48, -128, 6);
 	} else {
 		level_monster_update_anim(obj);
-		uint8_t al = m->flags & ~0x37;
-		if (al != 0x88) {
+		if ((m->flags & ~0x37) != 0x88) {
 			m->flags &= ~8;
 		}
 		int dy = MIN(g_vars.player_club_power, 25);
@@ -1209,6 +1218,7 @@ static bool level_handle_bonuses_found(struct object_t *obj, struct level_bonus_
 		g_vars.current_bonus.spr_num = 110 + num;
 		g_vars.current_bonus.y_pos -= 112;
 		level_add_object23_bonus(0, 0, 1);
+		++g_vars.level_current_secrets_count;
 	} else {
 		static uint8_t draw_counter = 0;
 		const int diff = abs(g_vars.level_draw_counter - draw_counter);
@@ -1290,6 +1300,7 @@ static bool level_collide_axe_bonuses(struct object_t *obj) {
 			continue;
 		}
 		memset(g_vars.level_bonuses_count_tbl, 0, 80);
+		int count = 0;
 		const uint16_t pos = bonus->pos;
 		for (int j = 0; j < MAX_LEVEL_BONUSES; ++j) {
 			struct level_bonus_t *bonus2 = &g_res.level.bonuses_tbl[j];
@@ -1304,8 +1315,13 @@ static bool level_collide_axe_bonuses(struct object_t *obj) {
 			}
 			if (g_vars.level_bonuses_count_tbl[j] == 0) {
 				++g_vars.level_bonuses_count_tbl[j];
+				++g_vars.level_current_secrets_count;
+				++count;
 			}
 		}
+		if (count == 0) {
+			return true;
+		}
 	}
 	return false;
 }
@@ -1334,11 +1350,11 @@ static void level_update_objects_axe() {
 	}
 }
 
-static void level_clear_boss_objects(int count) {
+static void level_update_objects_boss_energy(int count) {
 	if (count > 8) {
 		count = 8;
 	}
-	if (count != 0 && 0) {
+	if (count != 0) {
 		play_music(13);
 		for (int i = 0; i < count; ++i) {
 			struct object_t *obj = &g_vars.objects_tbl[108 + i];
@@ -1353,7 +1369,7 @@ static void level_clear_boss_objects(int count) {
 	}
 }
 
-static void level_update_objects_boss_level5_helper() {
+static void level_update_objects_boss_hit_player() {
 	--g_vars.bonus_energy_counter;
 	if (g_vars.bonus_energy_counter < 0) {
 		g_vars.bonus_energy_counter = 5;
@@ -1366,54 +1382,462 @@ static void level_update_objects_boss_level5_helper() {
 	}
 	g_vars.current_bonus.x_pos = g_vars.objects_tbl[1].x_pos;
 	g_vars.current_bonus.y_pos = g_vars.objects_tbl[1].y_pos - 48;
-	g_vars.current_bonus.spr_num = 0x2046;
+	g_vars.current_bonus.spr_num = 0x2046; /* bones */
 	const int x_vel = (g_vars.bonus_energy_counter & 1) != 0 ? -48 : 48;
 	const int y_vel = -128;
 	level_add_object23_bonus(x_vel, y_vel, 1);
 }
 
-static void level_update_boss_gorilla() {
-	const int x = (g_vars.boss.x_pos >> 4) + g_res.level.end_x_pos;
-	if (x >= 0) {
-		if (g_res.level.boss_xmin <= x && g_res.level.boss_xmax >= x) {
-			g_res.level.end_x_pos = x;
+static void level_update_boss_gorilla_collide_proj(struct object_t *obj_player, struct object_t *obj) {
+	if (obj->spr_num == 0xFFFF || (obj->spr_num & 0x2000) == 0) {
+		return;
+	}
+	if (!level_objects_collide(obj_player, obj)) {
+		return;
+	}
+	g_vars.boss.unk_counter -= 4 - g_res.level.boss_counter;
+	if (g_vars.boss.unk_counter < 0) {
+		g_vars.boss.unk_counter = 0;
+	}
+	level_update_objects_boss_hit_player();
+	obj_player->hit_counter = 44;
+	g_vars.player_anim_0x40_flag = 0;
+	obj_player->data.p.y_velocity = -128;
+	obj_player->x_friction = 3;
+	obj_player->x_velocity = (g_vars.objects_tbl[1].x_pos >= g_res.level.boss_x_pos) ? 128 : -128;
+	g_vars.player_gravity_flag = 0;
+}
+
+static void level_update_boss_gorilla_hit_player() {
+	if (g_vars.restart_level_flag != 0) {
+		return;
+	}
+	level_update_boss_gorilla_collide_proj(&g_vars.objects_tbl[1], g_vars.boss.obj2);
+	level_update_boss_gorilla_collide_proj(&g_vars.objects_tbl[1], g_vars.boss.obj1);
+	if (level_objects_collide(&g_vars.objects_tbl[1], g_vars.boss.obj3)) {
+		if (g_vars.player_jump_monster_flag != 0) {
+			g_vars.objects_tbl[1].data.p.y_velocity = (g_vars.input.key_up != 0) ? -128 : -64;
 		}
 	}
-	g_res.level.end_y_pos += (g_vars.boss.y_pos >> 4);
-	if (g_vars.boss.y_pos >= 0) {
-		const uint8_t bh = (g_res.level.end_y_pos >> 4);
-		const uint8_t bl = (g_res.level.end_x_pos >> 4);
-		const uint8_t tile_num = level_get_tile((bh << 8) | bl);
+}
+
+static void level_update_boss_gorilla_tick() {
+	if (g_vars.boss.unk_counter < UCHAR_MAX) {
+		++g_vars.boss.unk_counter;
+	}
+}
+
+static uint16_t level_update_boss_gorilla_find_pos(uint16_t num1, uint16_t num2) {
+	const uint16_t *p = boss_gorilla_spr_tbl;
+	const uint16_t *end = &boss_gorilla_spr_tbl[138];
+	while (p + 3 <= end) {
+		if (p[0] == num1 && p[1] == num2) {
+			return p[2]; /* dy,dx packed as a uint16_t */
+		}
+		p += 3;
+	}
+	print_warning("boss_gorilla spr range (%d,%d) not found", num1, num2);
+	return 0xFFFF;
+}
+
+static void level_update_boss_gorilla_init_objects(const uint16_t *p) {
+	g_vars.boss.parts[0].spr_num = *p++;
+	g_vars.boss.parts[1].spr_num = *p++;
+	uint16_t d;
+	int8_t dx, dy;
+
+	d = level_update_boss_gorilla_find_pos(g_vars.boss.parts[0].spr_num, g_vars.boss.parts[1].spr_num);
+	dx = d & 255;
+	if (g_vars.boss.hdir) {
+		dx = -dx;
+	}
+	g_vars.boss.parts[1].x_pos = dx + g_vars.boss.parts[0].x_pos;
+	dy = d >> 8;
+	g_vars.boss.parts[1].y_pos = dy + g_vars.boss.parts[0].y_pos;
+
+	g_vars.boss.parts[2].spr_num = *p++;
+	d = level_update_boss_gorilla_find_pos(g_vars.boss.parts[1].spr_num, g_vars.boss.parts[2].spr_num);
+	dx = d & 255;
+	if (g_vars.boss.hdir) {
+		dx = -dx;
+	}
+	g_vars.boss.parts[2].x_pos = dx + g_vars.boss.parts[1].x_pos;
+	dy = d >> 8;
+	g_vars.boss.parts[2].y_pos = dy + g_vars.boss.parts[1].y_pos;
+
+	g_vars.boss.parts[3].spr_num = *p++;
+	d = level_update_boss_gorilla_find_pos(g_vars.boss.parts[1].spr_num, g_vars.boss.parts[3].spr_num);
+	dx = d & 255;
+	if (g_vars.boss.hdir) {
+		dx = -dx;
+	}
+	g_vars.boss.parts[3].x_pos = dx + g_vars.boss.parts[1].x_pos;
+	dy = d >> 8;
+	g_vars.boss.parts[3].y_pos = dy + g_vars.boss.parts[1].y_pos;
+
+	g_vars.boss.parts[4].spr_num = *p++;
+	d = level_update_boss_gorilla_find_pos(g_vars.boss.parts[1].spr_num, g_vars.boss.parts[4].spr_num);
+	dx = d & 255;
+	if (g_vars.boss.hdir) {
+		dx = -dx;
+	}
+	g_vars.boss.parts[4].x_pos = dx + g_vars.boss.parts[1].x_pos;
+	dy = d >> 8;
+	g_vars.boss.parts[4].y_pos = dy + g_vars.boss.parts[1].y_pos;
+
+	if (g_vars.boss.anim_num & 0x40) {
+		g_vars.boss.parts[1].y_pos += 2;
+		++g_vars.boss.parts[2].y_pos;
+		++g_vars.boss.parts[4].y_pos;
+		++g_vars.boss.parts[3].y_pos;
+	}
+	if (g_vars.boss.hdir) {
+		g_vars.boss.parts[0].spr_num |= 0x8000;
+		g_vars.boss.parts[1].spr_num |= 0x8000;
+		g_vars.boss.parts[2].spr_num |= 0x8000;
+		g_vars.boss.parts[3].spr_num |= 0x8000;
+		g_vars.boss.parts[4].spr_num |= 0x8000;
+	}
+	for (int i = 0; i < 5; ++i) {
+		struct object_t *obj = &g_vars.objects_tbl[103 + i];
+		const uint16_t addr = *p++;
+		if (addr == 0xA609) {
+			g_vars.boss.obj1 = obj;
+		}
+		if (addr == 0xA60F) {
+			g_vars.boss.obj2 = obj;
+		}
+		if (addr == 0xA603) {
+			g_vars.boss.obj3 = obj;
+		}
+		assert(addr == 0xA5F7 || addr == 0xA5FD || addr == 0xA603 || addr == 0xA609 || addr == 0xA60F);
+		const int num = (addr - 0xA5F7) / 6;
+		obj->x_pos = g_vars.boss.parts[num].x_pos;
+		obj->y_pos = g_vars.boss.parts[num].y_pos;
+		obj->spr_num = g_vars.boss.parts[num].spr_num;
+	}
+}
+
+static bool level_update_boss_gorilla_collides_obj3(struct object_t *obj) {
+	if (obj->spr_num == 0xFFFF) {
+		return false;
+	}
+	const int spr_num = g_vars.boss.obj1->spr_num & 0x1FFF;
+	if ((spr_num == 0x196 || spr_num == 0x195) && level_objects_collide(obj, g_vars.boss.obj1)) {
+		obj->spr_num = 0xFFFF;
+		return false;
+	}
+	return level_objects_collide(obj, g_vars.boss.obj3);
+}
+
+static void level_update_boss_gorilla_helper2() {
+	for (int i = 0; i < 6; ++i) {
+		if (i == 1) {
+			continue;
+		}
+		struct object_t *obj = &g_vars.objects_tbl[i];
+		if (!level_update_boss_gorilla_collides_obj3(obj)) {
+			continue;
+		}
+		if (abs(g_vars.level_draw_counter - g_vars.boss.draw_counter) <= 22) {
+			break;
+		}
+		g_vars.boss.draw_counter = g_vars.level_draw_counter;
+		for (int j = 103; j <= 107; ++j) {
+			g_vars.objects_tbl[j].spr_num |= 0x4000;
+		}
+		g_vars.player_flying_flag = 0;
+		level_update_boss_gorilla_tick();
+		g_res.level.boss_energy -= g_vars.player_club_power;
+		if (g_res.level.boss_energy < 0) {
+			g_res.level.boss_state = 6;
+			g_vars.boss.y_velocity = -240;
+			break;
+		}
+		if (g_vars.player_club_power > 20) {
+			g_vars.boss.x_velocity = (g_res.level.boss_x_pos >= g_vars.objects_tbl[1].x_pos) ? 48 : -48;
+			g_vars.boss.y_velocity = (g_vars.boss.y_velocity > 0) ? -128 : -64;
+			g_res.level.boss_state = 5;
+		}
+		g_vars.boss.state_counter = 0;
+		obj->spr_num = 0xFFFF;
+		break;
+	}
+}
+
+static void level_update_boss_gorilla() {
+	const int x = (g_vars.boss.x_velocity >> 4) + g_res.level.boss_x_pos;
+	if (x >= 0) {
+		if (g_res.level.boss_xmin <= x && g_res.level.boss_xmax >= x) {
+			g_res.level.boss_x_pos = x;
+		}
+	}
+	g_res.level.boss_y_pos += (g_vars.boss.y_velocity >> 4);
+	if (g_vars.boss.y_velocity >= 0) {
+		const uint16_t pos = ((g_res.level.boss_y_pos >> 4) << 8) | (g_res.level.boss_x_pos >> 4);
+		const uint8_t tile_num = level_get_tile(pos);
 		if (g_res.level.tile_attributes1[tile_num] != 0) {
-			g_res.level.end_y_pos &= ~15;
-			if (g_vars.boss.y_pos != 0) {
+			g_res.level.boss_y_pos &= ~15;
+			if (g_vars.boss.y_velocity != 0) {
 				g_vars.shake_screen_counter = 7;
 			}
-			g_vars.boss.y_pos = 0;
-			g_vars.boss.x_pos = 0;
+			g_vars.boss.y_velocity = 0;
+			g_vars.boss.x_velocity = 0;
 		} else {
-			if (g_vars.boss.y_pos < 224) {
-				g_vars.boss.y_pos += 16;
+			if (g_vars.boss.y_velocity < 224) {
+				g_vars.boss.y_velocity += 16;
 			}
 		}
 	} else {
-		if (g_vars.boss.y_pos < 224) {
-			g_vars.boss.y_pos += 16;
+		if (g_vars.boss.y_velocity < 224) {
+			g_vars.boss.y_velocity += 16;
 		}
 	}
-	g_vars.boss.hdir = (g_vars.objects_tbl[1].x_pos < g_res.level.end_x_pos) ? 1 : 0;
-	g_vars.boss.x_dist = abs(g_vars.objects_tbl[1].x_pos - g_res.level.end_x_pos);
+	g_vars.boss.hdir = (g_res.level.boss_x_pos < g_vars.objects_tbl[1].x_pos);
+	g_vars.boss.x_dist = abs(g_vars.objects_tbl[1].x_pos - g_res.level.boss_x_pos);
 	if (g_vars.boss.x_dist > 400) {
 		return;
 	}
-	if (abs(g_vars.objects_tbl[1].y_pos - g_res.level.end_y_pos) > 250) {
+	if (abs(g_vars.objects_tbl[1].y_pos - g_res.level.boss_y_pos) > 250) {
 		return;
 	}
-	print_warning("level_update_boss unimplemented end_pos %d,%d", g_res.level.end_x_pos, g_res.level.end_y_pos);
+	if (g_res.level.boss_state == 0) {
+		if (g_vars.boss.x_dist >= 250) {
+			g_vars.boss.unk_counter = 0;
+			static const uint8_t data_st0[] = {
+				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0xF4
+			};
+			g_vars.boss.next_anim = data_st0;
+		} else {
+			g_vars.boss.state_counter = 0;
+			g_res.level.boss_state = 1;
+		}
+	} else if (g_res.level.boss_state == 1) {
+		if (g_vars.boss.x_dist >= 250) {
+			g_res.level.boss_state = 0;
+		} else {
+			++g_vars.boss.state_counter;
+			if (g_res.level.boss_energy < 60) {
+				g_res.level.boss_state = 2;
+			} else {
+				static const uint8_t data_st1[] = {
+					0x00, 0x00, 0x00, 0x40, 0x40, 0x40, 0xFA
+				};
+				g_vars.boss.next_anim = data_st1;
+				if (g_vars.boss.state_counter >= 110) {
+					g_res.level.boss_state = 1;
+					level_update_boss_gorilla_tick();
+					g_vars.boss.state_counter = 0;
+				} else if (g_vars.player_anim_0x40_flag != 0 && (g_vars.level_draw_counter & 7) == 0) {
+					level_update_boss_gorilla_tick();
+				} else if (g_vars.boss.unk_counter >= 10) {
+					g_res.level.boss_state = 3;
+					g_vars.boss.state_counter = 0;
+				} else if (g_vars.boss.unk_counter > 3) {
+					g_res.level.boss_state = 2;
+					g_vars.boss.state_counter = 0;
+				}
+			}
+		}
+	} else if (g_res.level.boss_state == 2) {
+		++g_vars.boss.state_counter;
+		if (g_vars.boss.state_counter != 64) {
+			if (g_vars.boss.state_counter > 64) {
+				if (g_vars.boss.y_velocity > 0) {
+					static const uint8_t data_st2a[] = {
+						0x04, 0xFF
+					};
+					static const uint8_t data_st2b[] = {
+						0x07, 0xFF
+					};
+					g_vars.boss.next_anim = (g_res.level.boss_energy >= 100) ? data_st2a : data_st2b;
+				}
+				if (g_vars.boss.x_dist <= 80) {
+					g_vars.boss.state_counter = 0;
+					g_res.level.boss_state = 3;
+					g_vars.boss.unk_counter = 11;
+				} else if (g_vars.boss.state_counter == 80) {
+					static const uint8_t data_st2[] = {
+						0x03, 0xFF
+					};
+					g_vars.boss.next_anim = data_st2;
+					int dx = g_res.level.boss_x_pos - g_vars.objects_tbl[1].x_pos;
+					int x_vel = 48;
+					int y_vel = abs(dx);
+					if (y_vel > g_res.level.boss_counter * 80) {
+						y_vel = -96;
+					} else {
+						y_vel = (y_vel / 14) << 4;
+						x_vel = y_vel >> 1;
+						y_vel = -y_vel;
+					}
+					g_vars.boss.y_velocity = y_vel;
+					if (dx >= 0) {
+						x_vel = -x_vel;
+					}
+					g_vars.boss.x_velocity = x_vel;
+				} else if (g_vars.boss.state_counter > 80) {
+					if (g_vars.boss.y_velocity == 0) {
+						g_vars.boss.unk_counter = 3;
+						g_vars.boss.state_counter = 0;
+						g_res.level.boss_state = 1;
+					}
+				}
+			} else {
+				level_update_boss_gorilla_hit_player();
+				if (g_vars.boss.x_dist < 75) {
+					g_res.level.boss_state = 3;
+					g_vars.boss.state_counter = 0;
+				} else {
+					static const uint8_t data_st2[] = {
+						0x10, 0x50, 0x10, 0x11, 0x51, 0x11, 0x10, 0x50, 0x10, 0x11,
+						0x51, 0x11, 0x10, 0x50, 0x10, 0x11, 0x51, 0x11, 0x00, 0x00,
+						0x40, 0x40, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00, 0x40, 0x40,
+						0x00, 0x00, 0x40, 0x40, 0xDE
+					};
+					g_vars.boss.next_anim = data_st2;
+				}
+			}
+		} else {
+			level_update_boss_gorilla_hit_player();
+			g_vars.boss.y_velocity = -224;
+			if (g_res.level.boss_energy < 60 && g_vars.boss.x_dist < 80) {
+				g_res.level.boss_state = 4;
+				g_vars.boss.state_counter = 0;
+			}
+			static const uint8_t data_st2[] = {
+				0x03, 0xFF
+			};
+			g_vars.boss.next_anim = data_st2;
+		}
+	} else if (g_res.level.boss_state == 3) {
+		level_update_boss_gorilla_hit_player();
+		const int counter = (abs(g_res.level.boss_energy - 50) > 25) ? 66 : 154;
+		if (g_vars.boss.state_counter > counter) {
+			g_vars.boss.state_counter = 0;
+			g_res.level.boss_state = 2;
+		} else {
+			if (g_vars.boss.y_velocity == 0) {
+				if (g_vars.boss.x_dist < 100) {
+					if (g_vars.boss.x_dist <= 25) {
+						static const uint8_t data_st3[] = {
+							0x0D, 0x0D, 0x0E, 0x0E, 0xFC
+						};
+						g_vars.boss.next_anim = data_st3;
+					} else if (g_vars.boss.x_dist <= 35) {
+						g_res.level.boss_state = 4;
+						g_vars.boss.state_counter = 0;
+					} else {
+						if (g_vars.boss.unk_counter == 0) {
+							g_res.level.boss_state = 7;
+							g_vars.boss.state_counter = 0;
+						}
+						static const uint8_t data_st3[] = {
+							0x0D, 0x0D, 0x0C, 0x0C, 0xFC
+						};
+						g_vars.boss.next_anim = data_st3;
+					}
+				} else {
+					g_vars.boss.y_velocity = -81;
+					g_vars.boss.x_velocity = (g_vars.objects_tbl[1].x_pos > g_res.level.boss_x_pos) ? 80 : -80;
+				}
+			} else if (g_vars.boss.y_velocity < 0) {
+				static const uint8_t data_st3[] = {
+					0x03, 0xFF
+				};
+				g_vars.boss.next_anim = data_st3;
+			} else {
+				static const uint8_t data_st3[] = {
+					0x0D, 0x0D, 0x0D, 0x0E, 0x0E, 0x0E, 0xFA
+				};
+				g_vars.boss.next_anim = data_st3;
+			}
+		}
+	} else if (g_res.level.boss_state == 4) {
+		level_update_boss_gorilla_hit_player();
+		++g_vars.boss.state_counter;
+		if (g_vars.boss.state_counter > 66) {
+			g_res.level.boss_state = 3;
+			g_vars.boss.state_counter = 0;
+		} else {
+			static const uint8_t data_st4[] = {
+				0x12, 0x12, 0x52, 0x12, 0x0E, 0x0E, 0x4E, 0x0E, 0xF8
+			};
+			g_vars.boss.next_anim = data_st4;
+			if (g_vars.boss.y_velocity == 0) {
+				g_vars.shake_screen_counter = 4;
+			}
+		}
+	} else if (g_res.level.boss_state == 5) {
+		++g_vars.boss.state_counter;
+		if (g_vars.boss.state_counter > 19) {
+			g_vars.boss.state_counter = 0;
+			g_res.level.boss_state = 1;
+		} else {
+			static const uint8_t data_st5[] = {
+				0x05, 0xFF
+			};
+			g_vars.boss.next_anim = data_st5;
+		}
+	} else if (g_res.level.boss_state == 6) {
+		static const uint8_t data_st6[] = {
+			0x05, 0x05, 0x0F, 0x0F, 0xFC
+		};
+		g_vars.boss.next_anim = data_st6;
+		if (g_vars.boss.y_velocity >= 0) {
+			g_res.level.boss_state = 0xFF;
+			g_vars.level_completed_flag = 1;
+			g_vars.objects_tbl[103].spr_num = 0xFFFF;
+			g_vars.objects_tbl[104].spr_num = 0xFFFF;
+			g_vars.objects_tbl[105].spr_num = 0xFFFF;
+			g_vars.objects_tbl[106].spr_num = 0xFFFF;
+			g_vars.objects_tbl[107].spr_num = 0xFFFF;
+			return;
+		}
+	} else if (g_res.level.boss_state == 7) {
+		++g_vars.boss.state_counter;
+		if (g_vars.boss.state_counter > 44) {
+			g_res.level.boss_state = 1;
+		} else {
+			static const uint8_t data_st7[] = {
+				0x03, 0xFF
+			};
+			g_vars.boss.next_anim = data_st7;
+			if (g_vars.boss.y_velocity == 0) {
+				g_vars.boss.y_velocity = -97;
+				g_vars.boss.x_velocity = (g_vars.objects_tbl[1].x_pos > g_res.level.boss_x_pos) ? -48 : 48;
+			} else if (g_vars.boss.y_velocity > 0) {
+				static const uint8_t data_st7[] = {
+					0x04, 0xFF
+				};
+				g_vars.boss.next_anim = data_st7;
+			}
+		}
+	}
+	if (g_vars.boss.prev_anim != g_vars.boss.next_anim) {
+		g_vars.boss.prev_anim = g_vars.boss.next_anim;
+		g_vars.boss.current_anim = g_vars.boss.next_anim;
+	}
+	const uint8_t *p = g_vars.boss.current_anim;
+	while (1) {
+		const uint8_t num = *p;
+		if (num & 0x80) {
+			p += (int8_t)num;
+		} else {
+			g_vars.boss.current_anim = p + 1;
+			g_vars.boss.anim_num = num;
+			g_vars.boss.parts[0].x_pos = g_res.level.boss_x_pos;
+			g_vars.boss.parts[0].y_pos = g_res.level.boss_y_pos;
+			const uint16_t *p = &boss_gorilla_data[(num & ~0x40) * 20 / sizeof(uint16_t)];
+			level_update_boss_gorilla_init_objects(p);
+			level_update_boss_gorilla_helper2();
+			break;
+		}
+	}
 }
 
 static void level_update_boss_tree() {
-	level_clear_boss_objects((2 - g_vars.boss_level5.state) << 1);
+	level_update_objects_boss_energy((2 - g_vars.boss_level5.state) << 1);
 	struct object_t *obj_player = &g_vars.objects_tbl[1];
 	for (int i = 0; i < 5; ++i) {
 		struct boss_level5_proj_t *prj = &g_vars.boss_level5.proj_tbl[i];
@@ -1427,7 +1851,7 @@ static void level_update_boss_tree() {
 			obj_player->data.p.y_velocity = -128;
 			obj_player->x_friction = 3;
 			obj_player->x_velocity = -128;
-			level_update_objects_boss_level5_helper();
+			level_update_objects_boss_hit_player();
 			prj->spr_num = 0xFFFF;
 			obj->spr_num = 0xFFFF;
 		} else {
@@ -1474,7 +1898,7 @@ static void level_update_boss_tree() {
 		0x3B4, 0x79F, 0x1A7, 0x396, 0x78A, 0x1A8, 0x3B6, 0x79C, 0x1A9,
 		0x3E0, 0x795, 0x1B6, 0, 0, 0xFFFF
 	};
-	const uint16_t *p = &pos1_data[g_vars.boss_level5.unk5 * 6];
+	const uint16_t *p = &pos1_data[g_vars.boss_level5.spr106_pos * 6];
 	g_vars.objects_tbl[107].x_pos = p[0];
 	g_vars.objects_tbl[107].y_pos = p[1];
 	g_vars.objects_tbl[107].spr_num = p[2];
@@ -1484,20 +1908,20 @@ static void level_update_boss_tree() {
 	static const uint16_t pos3_data[] = {
 		0x3E3, 0x773, 0x1B0, 0x3E4, 0x771, 0x1B1, 0x3E4, 0x773, 0x1B2
 	};
-	const uint16_t *q = &pos3_data[g_vars.boss_level5.unk4 * 3];
+	const uint16_t *q = &pos3_data[g_vars.boss_level5.spr103_pos * 3];
 	g_vars.objects_tbl[103].x_pos = q[0];
 	g_vars.objects_tbl[103].y_pos = q[1];
 	g_vars.objects_tbl[103].spr_num = (g_vars.boss_level5.state != 0) ? 0xFFFF : q[2];
 	if ((g_vars.level_draw_counter & 3) == 0) {
-		++g_vars.boss_level5.unk4;
-		if (g_vars.boss_level5.unk4 > 2) {
-			g_vars.boss_level5.unk4 = 0;
+		++g_vars.boss_level5.spr103_pos;
+		if (g_vars.boss_level5.spr103_pos > 2) {
+			g_vars.boss_level5.spr103_pos = 0;
 		}
 	}
 	if (g_vars.boss_level5.unk1 >= 1) {
 		if (g_vars.boss_level5.unk1 == 1) {
 			g_vars.boss_level5.unk6 = 2;
-			--g_vars.boss_level5.unk5;
+			--g_vars.boss_level5.spr106_pos;
 			g_vars.boss_level5.counter += 5;
 		}
 		--g_vars.boss_level5.unk1;
@@ -1506,12 +1930,12 @@ static void level_update_boss_tree() {
 		if (g_vars.boss_level5.unk6 > 2) {
 			g_vars.boss_level5.unk6 = 0;
 		}
-		++g_vars.boss_level5.unk5;
-		if (g_vars.boss_level5.unk5 > 2) {
-			g_vars.boss_level5.unk5 = 0;
+		++g_vars.boss_level5.spr106_pos;
+		if (g_vars.boss_level5.spr106_pos > 2) {
+			g_vars.boss_level5.spr106_pos = 0;
 		}
 		uint8_t ah = 1;
-		if (g_vars.boss_level5.unk5 != 0) {
+		if (g_vars.boss_level5.spr106_pos != 0) {
 			ah = 3;
 			g_vars.shake_screen_counter = 4;
 			obj_player->x_pos += 2;
@@ -1547,9 +1971,9 @@ static void level_update_boss_tree() {
 					g_vars.player_anim_0x40_flag = 0;
 					obj_player->x_friction = 3;
 					obj_player->x_velocity = -128;
-					level_update_objects_boss_level5_helper();
-					level_update_objects_boss_level5_helper();
-					level_update_objects_boss_level5_helper();
+					level_update_objects_boss_hit_player();
+					level_update_objects_boss_hit_player();
+					level_update_objects_boss_hit_player();
 				}
 			}
 		}
@@ -1577,7 +2001,7 @@ static void level_update_boss_tree() {
 				g_vars.boss_level5.unk1 = 6;
 				if (g_vars.boss_level5.state < 2) {
 					g_vars.boss_level5.unk6 = 3;
-					g_vars.boss_level5.unk5 = 3;
+					g_vars.boss_level5.spr106_pos = 3;
 				}
 				--g_vars.boss_level5.energy;
 				if (g_vars.boss_level5.energy == 0) {
@@ -1596,7 +2020,7 @@ static void level_update_boss_tree() {
 			obj_player->data.p.y_velocity = -144;
 			obj_player->x_friction = 3;
 			obj_player->x_velocity = -160;
-			level_update_objects_boss_level5_helper();
+			level_update_objects_boss_hit_player();
 		}
 	}
 	if (g_vars.boss_level5.counter > 0) {
@@ -1604,10 +2028,16 @@ static void level_update_boss_tree() {
 	}
 }
 
-static void level_update_boss_minotaur_update_tiles(int count) {
+static void level_update_boss_minotaur_set_frame(int num) {
+	const int offset = (num * 6 + 20);
+	for (int y = 0; y < 7; ++y) {
+		for (int x = 0; x < 6; ++x) {
+			g_res.leveldat[(y << 8) + 12 + x] = g_res.leveldat[(y << 8) + offset + x];
+		}
+	}
 }
 
-static void level_update_boss_minotaur_helper() {
+static void level_update_boss_minotaur_add_spr_0x137() { /* boss defeated, bonus */
 	g_vars.current_bonus.x_pos = 185;
 	g_vars.current_bonus.y_pos = 30;
 	g_vars.current_bonus.spr_num = 0x2137;
@@ -1623,64 +2053,65 @@ static void level_update_boss_minotaur_helper() {
 	}
 }
 
-static void level_update_boss_minotaur_add_spr_0x1CA() {
+static void level_update_boss_minotaur_add_spr_0x1CA() { /* rock */
 	for (int i = 0; i < 32; ++i) {
 		struct object_t *obj = &g_vars.objects_tbl[23 + i];
-		if (obj->spr_num == 0xFFFF) {
+		if (obj->spr_num != 0xFFFF) {
 			continue;
 		}
 		obj->spr_num = 0x1CA;
 		obj->x_pos = 200;
 		obj->y_pos = 88;
+		obj->hit_counter = 0;
 		obj->data.t.counter = 132;
 		obj->data.t.ref = 0;
 		obj->x_velocity = -((random_get_number() & 15) << 3);
-		obj->data.t.unkE = 0;
+		obj->data.t.y_velocity = 0;
 		break;
 	}
 }
 
-static void level_update_boss_minotaur_add_spr_0x1CB() {
+static void level_update_boss_minotaur_add_spr_0x1CB() { /* ceiling chandelier */
 	for (int i = 0; i < 32; ++i) {
 		struct object_t *obj = &g_vars.objects_tbl[23 + i];
-		if (obj->spr_num == 0xFFFF) {
+		if (obj->spr_num != 0xFFFF) {
 			continue;
 		}
 		obj->spr_num = 0x1CB;
 		obj->x_pos = (random_get_number() & 0x7F) - 16;
 		obj->y_pos = 0;
+		obj->hit_counter = 0;
 		obj->data.t.counter = 66;
 		obj->data.t.ref = 0;
 		obj->x_velocity = 0;
-		obj->data.t.unkE = 0;
+		obj->data.t.y_velocity = 0;
 		break;
 	}
 }
 
 static void level_update_boss_minotaur() {
 	static const uint16_t data[] = {
-		0xA70F, 5, 0xA74E, 1, 0xA70F, 3, 0xA74E, 2, 0xA70F, 2, 0xA734, 1, 0xFFFF, 0xFFE8
+		0xA70F, 5, 0xA74E, 1, 0xA70F, 3, 0xA74E, 2, 0xA70F, 2, 0xA734, 1, 0xFFFF
 	};
 	if (!g_vars.boss_level9.seq) {
 		g_vars.boss_level9.anim = data;
-		g_vars.boss_level9.unk1 = 24;
-		g_vars.boss_level9.unk2 = 0;
-		g_vars.boss_level9.unk3 = 3;
+		g_vars.boss_level9.energy = 24;
+		g_vars.boss_level9.seq_counter = 0;
+		g_vars.boss_level9.hit_counter = 3;
 	}
-	level_clear_boss_objects(g_vars.boss_level9.unk1 >> 2);
-	if (g_vars.boss_level9.unk1 == 0) {
-		level_update_boss_minotaur_update_tiles(2);
+	level_update_objects_boss_energy(g_vars.boss_level9.energy >> 2);
+	if (g_vars.boss_level9.energy == 0) {
+		level_update_boss_minotaur_set_frame(2);
 		return;
 	}
-	if (g_vars.boss_level9.unk2 == 0) {
+	if (g_vars.boss_level9.seq_counter == 0) {
 		const uint16_t *p = g_vars.boss_level9.anim;
 		if (p[0] == 0xFFFF) {
-			p += (int16_t)p[1] / 2;
-			assert(p == data);
+			p = data;
 		}
 		assert(p[0] >= 0xA70F);
 		g_vars.boss_level9.seq = &boss_minotaur_seq_data[p[0] - 0xA70F];
-		g_vars.boss_level9.unk2 = p[1];
+		g_vars.boss_level9.seq_counter = p[1];
 		g_vars.boss_level9.anim = p + 2;
 	}
 	for (int i = 0; i < 4; ++i) {
@@ -1688,19 +2119,19 @@ static void level_update_boss_minotaur() {
 		if (obj->spr_num == 0xFFFF) {
 			continue;
 		}
-		if ((obj->x_pos >= 235) || obj->y_pos >= 80) {
+		if (obj->x_pos >= 235 || obj->y_pos >= 80) {
 			continue;
 		}
 		g_vars.boss_level9.seq = &boss_minotaur_seq_data[0x19];
-		if (g_vars.boss_level9.unk1 > 0) {
-			--g_vars.boss_level9.unk1;
+		if (g_vars.boss_level9.energy > 0) {
+			--g_vars.boss_level9.energy;
 		}
-		if (g_vars.boss_level9.unk1 == 0) {
-			level_update_boss_minotaur_helper();
+		if (g_vars.boss_level9.energy == 0) {
+			level_update_boss_minotaur_add_spr_0x137();
 		}
-		++g_vars.boss_level9.unk3;
-		g_vars.boss_level9.unk3 &= 3;
-		if (g_vars.boss_level9.unk3 == 0) {
+		++g_vars.boss_level9.hit_counter;
+		g_vars.boss_level9.hit_counter &= 3;
+		if (g_vars.boss_level9.hit_counter == 0) {
 			g_vars.boss_level9.seq = &boss_minotaur_seq_data[0x25];
 		}
 		break;
@@ -1718,11 +2149,11 @@ static void level_update_boss_minotaur() {
 			++p;
 		} else if ((*p & 0x80) == 0) {
 			++g_vars.boss_level9.seq;
-			level_update_boss_minotaur_update_tiles(*p);
+			level_update_boss_minotaur_set_frame(*p);
 			break;
 		} else {
-			if (g_vars.boss_level9.unk2 > 0) {
-				--g_vars.boss_level9.unk2;
+			if (g_vars.boss_level9.seq_counter > 0) {
+				--g_vars.boss_level9.seq_counter;
 			}
 			p += (int8_t)*p;
 			g_vars.boss_level9.seq = p;
@@ -1808,7 +2239,7 @@ extern void monster_func1(int type, struct object_t *obj); /* update */
 extern bool monster_func2(int type, struct level_monster_t *m); /* init */
 
 static void level_update_objects_monsters() {
-	if (g_res.level.boss_flag != 0xFF) {
+	if (g_res.level.boss_state != 0xFF) {
 		level_update_boss_gorilla();
 	}
 	if (g_vars.level_num == 5 && (g_res.level.scrolling_mask & ~1) == 0) {
@@ -1960,30 +2391,29 @@ static void level_update_objects_bonuses() {
 			obj->x_pos = 0;
 			obj->x_velocity = -obj->x_velocity;
 		}
-		const int dy = obj->data.p.y_velocity >> 4;
-		obj->y_pos += dy;
-		int dx = obj->data.p.y_velocity + 9;
-		if (dx < 256) {
-			obj->data.p.y_velocity = dx;
+		obj->y_pos += (obj->data.t.y_velocity >> 4);
+		const int dy = obj->data.t.y_velocity + 9;
+		if (dy < 256) {
+			obj->data.t.y_velocity = dy;
 		}
 		const int num = obj->spr_num & 0x1FFF;
 		if (num == 229) {
 			continue;
 		}
-		if (num == 300) {
+		if (num == 300 || num == 306 || num == 308 || num == 310) {
 			if (obj->data.t.counter > 50) {
 				obj->data.t.counter = 50;
 			}
 			continue;
 		}
-		uint8_t bl = obj->x_pos >> 4;
-		uint8_t bh = obj->y_pos >> 4;
+		const uint16_t pos = ((obj->y_pos >> 4) << 8) | (obj->x_pos >> 4);
 		if (dy > 0) {
-			const int tile_num = level_get_tile(bh * 256 + bl);
+			const int tile_num = level_get_tile(pos);
 			uint8_t al = g_res.level.tile_attributes1[tile_num];
 			if (al != 0) {
-				obj->data.p.y_velocity = -obj->data.p.y_velocity;
-				obj->data.p.y_velocity >>= 1;
+				/* bounce on the ground */
+				obj->data.t.y_velocity = -obj->data.t.y_velocity;
+				obj->data.t.y_velocity >>= 1;
 				const bool x_direction = (obj->x_velocity < 0);
 				const int dx = (obj->x_velocity < 0) ? -8 : 8;
 				obj->x_velocity -= dx;
@@ -1992,8 +2422,7 @@ static void level_update_objects_bonuses() {
 				}
 			}
 		} else {
-			bh -= 1;
-			const int tile_num = level_get_tile(bh * 256 + bl);
+			const int tile_num = level_get_tile(pos - 0x100);
 			uint8_t al = g_res.level.tile_attributes0[tile_num];
 			if (al != 0) {
 				obj->x_velocity = -obj->x_velocity;
@@ -2801,6 +3230,18 @@ update_pos:
 	}
 }
 
+static void level_add_object23_bones() {
+	g_vars.current_bonus.x_pos = g_vars.objects_tbl[1].x_pos;
+	g_vars.current_bonus.y_pos = g_vars.objects_tbl[1].y_pos - 48;
+	const int count = g_vars.player_energy * 6 + g_vars.bonus_energy_counter;
+	if (count != 0) {
+		g_vars.player_energy = 0;
+		g_vars.bonus_energy_counter = 0;
+		g_vars.current_bonus.spr_num = 0x2046; /* bones */
+		level_add_object23_bonus(48, -128, count);
+	}
+}
+
 static void level_clear_item(struct object_t *obj) {
 	struct level_item_t *item = obj->data.t.ref;
 	if (item) {
@@ -2912,8 +3353,20 @@ static void level_update_player_collision() {
 		const int num = (obj->spr_num & 0x1FFF) - 53;
 		obj->spr_num = 0xFFFF;
 		if (num == 226) {
+			if (g_vars.level_num == 2) {
+				g_vars.level_num = 12;
+			} else if (g_vars.level_num == 13) {
+				g_vars.level_num = 2;
+			} else if (g_vars.level_num == 6) {
+				g_vars.level_num = 14;
+			} else if (g_vars.level_num == 15) {
+				g_vars.level_num = 6;
+			}
 			g_vars.level_completed_flag = 1;
 			return;
+		} else if (num == 258) {
+			g_vars.level_completed_flag = 0xFF; /* game completed */
+			return;
 		} else if (num == 228) { /* checkpoint */
 			g_vars.tilemap_start_x_pos = g_vars.objects_tbl[1].x_pos;
 			g_vars.tilemap_start_y_pos = g_vars.objects_tbl[1].y_pos;
@@ -2979,8 +3432,8 @@ static void level_update_player_collision() {
 			level_clear_item(obj);
 		} else if (num <= 64) { /* food */
 			play_sound(4);
-			if (obj->data.t.unkE >= 128) {
-				obj->data.t.unkE = -obj->data.t.unkE;
+			if (obj->data.t.y_velocity >= 128) {
+				obj->data.t.y_velocity = -obj->data.t.y_velocity;
 				int x = 32;
 				if ((random_get_number() & 1) != 0) {
 					x = -x;
@@ -2993,6 +3446,9 @@ static void level_update_player_collision() {
 				++g_vars.level_items_count_tbl[index];
 				++g_vars.level_items_total_count;
 				level_add_object75_score(obj, score_spr_lut[index] + 74);
+				if (obj->data.t.ref) {
+					++g_vars.level_complete_bonuses_count;
+				}
 			}
 		} else if (num <= 74) {
 			play_sound(8);
@@ -3017,15 +3473,7 @@ static void level_update_player_collision() {
 			g_vars.objects_tbl[1].hit_counter = 44;
 			g_vars.objects_tbl[1].data.p.special_anim_num = 0;
 			g_vars.objects_tbl[1].data.p.current_anim_num = 8;
-			g_vars.current_bonus.x_pos = g_vars.objects_tbl[1].x_pos;
-			g_vars.current_bonus.y_pos = g_vars.objects_tbl[1].y_pos - 48;
-			const int count = g_vars.player_energy * 6 + g_vars.bonus_energy_counter;
-			if (count != 0) {
-				g_vars.player_energy = 0;
-				g_vars.bonus_energy_counter = 0;
-				g_vars.current_bonus.spr_num = 0x2046;
-				level_add_object23_bonus(48, -128, count);
-			}
+			level_add_object23_bones();
 			g_vars.shake_screen_counter = 7;
 			level_clear_item(obj);
 			level_add_object75_score(obj, 228);
@@ -3102,6 +3550,23 @@ static void level_update_player_collision() {
 				g_vars.light.state = 0;
 			}
 			level_clear_item(obj);
+		} else if (num == 458 || num == 459) { /* boss projectiles */
+			if (g_options.cheats & CHEATS_UNLIMITED_ENERGY) {
+				continue;
+			}
+			if (g_vars.player_energy < 1) {
+				level_player_die();
+			} else {
+				play_sound(1);
+				g_vars.objects_tbl[1].hit_counter = 44;
+				g_vars.objects_tbl[1].data.p.special_anim_num = 0;
+				g_vars.objects_tbl[1].data.p.current_anim_num = 8;
+				--g_vars.player_energy;
+				const uint8_t energy = g_vars.player_energy;
+				g_vars.player_energy = 1;
+				level_add_object23_bones();
+				g_vars.player_energy = energy;
+			}
 		}
 	}
 }
@@ -3192,8 +3657,8 @@ static void level_update_gates() {
 				g_vars.boss_level5.unk1 = 0;
 				g_vars.boss_level5.energy = 10;
 				g_vars.boss_level5.state = 0;
-				g_vars.boss_level5.unk4 = 0;
-				g_vars.boss_level5.unk5 = 1;
+				g_vars.boss_level5.spr103_pos = 0;
+				g_vars.boss_level5.spr106_pos = 1;
 				g_vars.boss_level5.unk6 = 0;
 				g_vars.boss_level5.counter = 110;
 				g_vars.boss_level5.unk8 = 8;
@@ -3416,12 +3881,18 @@ static void level_draw_objects() {
 		int spr_y_pos = obj->y_pos - ((g_vars.tilemap.y << 4) + g_vars.tilemap.scroll_dy);
 		int spr_h = spr_size_tbl[2 * spr_num + 1];
 		spr_y_pos -= spr_h;
+		if (spr_y_pos > TILEMAP_SCREEN_H || spr_y_pos + spr_h < 0) {
+			continue;
+		}
 		int spr_x_pos = obj->x_pos - ((g_vars.tilemap.x << 4) + g_vars.tilemap.scroll_dx);
 		int spr_w = spr_offs_tbl[2 * spr_num];
 		if (spr_hflip) {
 			spr_w = spr_size_tbl[2 * spr_num] - spr_w;
 		}
 		spr_x_pos -= spr_w;
+		if (spr_x_pos > TILEMAP_SCREEN_W || spr_x_pos + spr_w < 0) {
+			continue;
+		}
 		video_draw_sprite(spr_num, spr_x_pos, spr_y_pos, spr_hflip);
 		obj->spr_num |= 0x2000;
 		obj->spr_num &= ~0x4000;
@@ -3525,13 +3996,32 @@ static void level_player_death_animation() {
 
 static void level_completed_bonuses_animation_draw_score() {
 	const int score_digits = _score_8_digits ? 8 : 7;
-	const int offset = _score_8_digits ? 0x246 : 0x247;
+	video_draw_string2(0x230, "SCORE");
 	int score = g_vars.score * 10;
 	for (int i = 0; i < score_digits; ++i) {
 		const int digit = score % 10;
 		score /= 10;
-		video_draw_number(offset + (score_digits - 1 - i) * 16 / 8, digit);
+		video_draw_number(0x23C + (score_digits - 1 - i) * 16 / 8, digit);
 	}
+	if (g_res.dos_demo) {
+		return;
+	}
+	video_draw_string2(0x410, "LEVEL COMPLETED");
+	int percentage = 100;
+	const int total = g_vars.level_complete_secrets_count + g_vars.level_complete_bonuses_count;
+	if (total != 0) {
+		const int current = g_vars.level_current_secrets_count + g_vars.level_current_bonuses_count;
+		percentage = (current * 100) / total;
+	}
+	for (int i = 0; i < 3; ++i) {
+		const int digit = percentage % 10;
+		percentage /= 10;
+		video_draw_number(0x430 + (2 - i) * 16 / 8, digit);
+		if (percentage == 0) {
+			break;
+		}
+	}
+	video_draw_character_spr(0x436, 0x1A);
 }
 
 static void level_completed_bonuses_animation_fixup_object4_spr_num() {
@@ -3559,10 +4049,10 @@ static int level_completed_bonuses_animation_helper() {
 			if (obj->spr_num == 0xFFFF) {
 				continue;
 			}
-			int y_velocity = obj->data.p.y_velocity;
+			int y_velocity = obj->data.t.y_velocity;
 			if (y_velocity < 128) {
 				y_velocity += 8;
-				obj->data.p.y_velocity = y_velocity;
+				obj->data.t.y_velocity = y_velocity;
 			}
 			obj->y_pos += y_velocity >> 4;
 			++bp;
@@ -3691,7 +4181,7 @@ static void level_completed_bonuses_animation() {
 						obj->spr_num = 110 + di;
 						obj->x_pos = 155;
 						obj->y_pos = 0;
-						obj->data.p.y_velocity = 0;
+						obj->data.t.y_velocity = 0;
 						--g_vars.level_items_count_tbl[di];
 						++di;
 						break;
diff --git a/p2/resource.c b/p2/resource.c
index 4275fb1..c0653d1 100644
--- a/p2/resource.c
+++ b/p2/resource.c
@@ -251,9 +251,9 @@ void load_leveldat(const uint8_t *p, struct level_t *level) {
 	g_res.level.boss_xmax = READ_LE_UINT16(p); p += 2;
 	g_res.level.boss_counter = *p++;
 	g_res.level.boss_energy = READ_LE_UINT16(p); p += 2;
-	g_res.level.boss_flag = *p++;
-	g_res.level.end_x_pos = READ_LE_UINT16(p); p += 2;
-	g_res.level.end_y_pos = READ_LE_UINT16(p); p += 2;
+	g_res.level.boss_state = *p++;
+	g_res.level.boss_x_pos = READ_LE_UINT16(p); p += 2;
+	g_res.level.boss_y_pos = READ_LE_UINT16(p); p += 2;
 	const int total = p - g_res.leveldat;
 	print_debug(DBG_RESOURCE, "level total offset %d", total);
 }
diff --git a/p2/resource.h b/p2/resource.h
index 24aa5b8..089e2b3 100644
--- a/p2/resource.h
+++ b/p2/resource.h
@@ -153,9 +153,9 @@ struct level_t {
 	uint16_t boss_xmax;
 	uint8_t boss_counter;
 	uint16_t boss_energy;
-	uint8_t boss_flag; /* !=255: has boss */
-	uint16_t end_x_pos;
-	uint16_t end_y_pos;
+	uint8_t boss_state; /* !=255: has boss */
+	uint16_t boss_x_pos;
+	uint16_t boss_y_pos;
 };
 
 struct resource_t {
diff --git a/p2/screen.c b/p2/screen.c
index c0a83f6..313a40c 100644
--- a/p2/screen.c
+++ b/p2/screen.c
@@ -88,6 +88,22 @@ void video_draw_number(int offset, int num) {
 	decode_planar(fnt + num * 88, g_res.vga + y * GAME_SCREEN_W + x, GAME_SCREEN_W, 16, 11, 0);
 }
 
+void video_draw_character_spr(int offset, uint8_t chr) {
+	const int y = (offset * 8) / 320;
+	const int x = (offset * 8) % 320;
+	video_draw_sprite(241 + chr, x, y, 0);
+}
+
+void video_draw_string2(int offset, const char *s) {
+	while (*s) {
+		const uint8_t chr = *s++;
+		if (chr != ' ') {
+			video_draw_character_spr(offset, chr - 0x41);
+		}
+		offset += 2;
+	}
+}
+
 void video_clear() {
 	memset(g_res.vga, 0, GAME_SCREEN_W * GAME_SCREEN_H);
 }
diff --git a/p2/sound.c b/p2/sound.c
index d2e6829..2c6f0da 100644
--- a/p2/sound.c
+++ b/p2/sound.c
@@ -57,6 +57,7 @@ struct mixerchannel_t {
 static const int _rate = SYS_AUDIO_FREQ;
 static struct mixerchannel_t _channel;
 static ModPlugFile *_mpf;
+static int _music_num;
 
 static uint16_t sound_offsets_tbl[MAX_SOUNDS];
 
@@ -99,6 +100,7 @@ void sound_init() {
 		sound_offsets_tbl[i] = offset;
 		offset += sound_sizes_tbl[i];
 	}
+	_music_num = -1;
 	g_sys.start_audio(mix, 0);
 }
 
@@ -130,6 +132,9 @@ void play_music(int num) {
 	if (g_res.dos_demo) { /* no .TRK files with demo */
 		return;
 	}
+	if (_music_num == num) {
+		return;
+	}
 	const char *filename = trk_names_tbl[num];
 	if (filename) {
 		print_debug(DBG_MIXER, "play_music '%s'", filename);
@@ -145,6 +150,7 @@ void play_music(int num) {
 				print_debug(DBG_MIXER, "Loaded module '%s'", ModPlug_GetName(_mpf));
 			}
 			free(data);
+			_music_num = num;
 		}
 		g_sys.unlock_audio();
 	}
diff --git a/p2/staticres.c b/p2/staticres.c
index e329c4d..3da754d 100644
--- a/p2/staticres.c
+++ b/p2/staticres.c
@@ -455,46 +455,30 @@ const uint8_t boss_minotaur_seq_data[] = {
 	0x03,0x03,0x03,0x03,0xF1,0x00,0x00,0xFF,0x03,0x03,0xFE,0x03,0x00,0x00,0x00,0x03,
 	0x03,0x03,0x03,0x00,0xFE,0x00,0x03,0x03,0x03,0x00,0x00,0x03,0x03,0x03,0xE7,0x04,
 	0x04,0x04,0x04,0x04,0x04,0x04,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x00,0x00,0x00,
-	0xFF,0x00,0x00,0x00,0x00,0xEA,0xA2,0x01,0x9A,0x01,0x95,0x01,0x9F,0x01,0xA0,0x01,
-	0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,0x9A,0x01,0x96,0x01,
-	0x9D,0x01,0xA0,0x01,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,
-	0x9A,0x01,0x96,0x01,0x9C,0x01,0xA0,0x01,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,
-	0x09,0xA6,0xA1,0x01,0x99,0x01,0x96,0x01,0x9D,0x01,0x9D,0x81,0x0F,0xA6,0x03,0xA6,
-	0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,0x9B,0x01,0x96,0x01,0x9D,0x01,0x9D,0x81,
-	0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,0x99,0x01,0x98,0x81,
-	0x9E,0x01,0x9E,0x81,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,
-	0x9A,0x01,0x98,0x01,0x9C,0x01,0x9D,0x81,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,
-	0x09,0xA6,0xA2,0x01,0x9A,0x01,0x95,0x01,0x9E,0x01,0x9E,0x81,0x0F,0xA6,0x03,0xA6,
-	0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,0x99,0x01,0x95,0x01,0x9E,0x01,0x9D,0x81,
-	0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA3,0x01,0x99,0x01,0x95,0x01,
-	0x9E,0x01,0x9D,0x81,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,
-	0x99,0x01,0x95,0x01,0x9E,0x01,0xA0,0x01,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,
-	0x09,0xA6,0xA3,0x01,0x99,0x01,0x95,0x01,0x9D,0x01,0xA0,0x01,0x0F,0xA6,0x03,0xA6,
-	0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA3,0x01,0x9B,0x01,0x95,0x01,0x9E,0x01,0x9D,0x81,
-	0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA3,0x01,0x9B,0x01,0x95,0x01,
-	0x9D,0x01,0x9D,0x81,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA3,0x01,
-	0x9B,0x01,0x95,0x01,0x9D,0x01,0xA0,0x01,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,
-	0x09,0xA6,0xA2,0x01,0x9A,0x01,0x98,0x01,0x9C,0x01,0x9D,0x81,0x0F,0xA6,0x03,0xA6,
-	0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,0x9A,0x01,0x97,0x01,0x9E,0x01,0x9D,0x81,
-	0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA2,0x01,0x9A,0x01,0x97,0x01,
-	0x9D,0x01,0x9E,0x81,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0xF7,0xA5,0x09,0xA6,0xA3,0x01,
-	0x9A,0x01,0x95,0x01,0xA0,0x81,0x9D,0x81,0x0F,0xA6,0x03,0xA6,0xFD,0xA5,0x09,0xA6,
-	0xF7,0xA5,0xA2,0x01,0x99,0x01,0xF8,0xE9,0xA2,0x01,0x9A,0x01,0xFB,0xEB,0xA2,0x01,
-	0x9B,0x01,0xF6,0xE8,0xA1,0x01,0x99,0x01,0xF6,0xDB,0xA1,0x01,0x9A,0x01,0x01,0xDD,
-	0xA1,0x01,0x9B,0x01,0xF3,0xDA,0xA3,0x01,0x99,0x01,0xED,0xF0,0xA3,0x01,0x9A,0x01,
-	0xF0,0xF2,0xA3,0x01,0x9B,0x01,0xEB,0xF0,0x99,0x01,0x95,0x01,0xFF,0xE8,0x9A,0x01,
-	0x95,0x01,0xFB,0xEA,0x9B,0x01,0x95,0x01,0xF8,0xF7,0x99,0x01,0x96,0x01,0xFF,0xE8,
-	0x9A,0x01,0x96,0x01,0xFB,0xEA,0x9B,0x01,0x96,0x01,0xF8,0xF7,0x99,0x01,0x97,0x01,
-	0xFF,0xE8,0x9A,0x01,0x97,0x01,0xFB,0xEA,0x9B,0x01,0x97,0x01,0xF8,0xF7,0x99,0x01,
-	0x98,0x01,0xFF,0xE8,0x9A,0x01,0x98,0x01,0xFB,0xEA,0x9B,0x01,0x98,0x01,0xF8,0xF7,
-	0x99,0x01,0x98,0x81,0xFF,0xE8,0x9A,0x01,0x98,0x81,0xFB,0xEA,0x9B,0x01,0x98,0x81,
-	0xF8,0xF7,0x99,0x01,0x9C,0x01,0xE2,0xEC,0x99,0x01,0x9D,0x01,0xDD,0xF1,0x99,0x01,
-	0x9E,0x01,0xD6,0xE9,0x99,0x01,0x9F,0x01,0xE8,0x0C,0x9A,0x01,0x9C,0x01,0xE2,0xEC,
-	0x9A,0x01,0x9D,0x01,0xE0,0xF1,0x9A,0x01,0x9E,0x01,0xD4,0xEA,0x9A,0x01,0x9F,0x01,
-	0xEA,0x0F,0x9B,0x01,0x9C,0x01,0xDE,0xF8,0x9B,0x01,0x9D,0x01,0xDC,0x02,0x9B,0x01,
-	0x9E,0x01,0xCE,0xFB,0x9B,0x01,0x9F,0x01,0xE6,0x1D,0x99,0x01,0x9D,0x81,0x21,0xEB,
-	0x99,0x01,0x9E,0x81,0x2C,0xE4,0x99,0x01,0xA0,0x01,0x12,0x10,0x9A,0x01,0x9D,0x81,
-	0x18,0xEE,0x9A,0x01,0x9E,0x81,0x29,0xEA,0x9A,0x01,0xA0,0x01,0x09,0x13,0x9B,0x01,
-	0x9D,0x81,0x1A,0xF9,0x9B,0x01,0x9E,0x81,0x29,0xF3,0x9B,0x01,0xA0,0x01,0x0C,0x1E,
-	0x9A,0x01,0xA0,0x81,0xEC,0x16
+	0xFF,0x00,0x00,0x00,0x00,0xEA
+};
+const uint16_t boss_gorilla_data[] = {
+	0x01A2,0x019A,0x0195,0x019F,0x01A0,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x019A,0x0196,0x019D,0x01A0,0xA60F,
+	0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x019A,0x0196,0x019C,0x01A0,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A1,0x0199,
+	0x0196,0x019D,0x819D,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x019B,0x0196,0x019D,0x819D,0xA60F,0xA603,0xA5FD,
+	0xA5F7,0xA609,0x01A2,0x0199,0x8198,0x019E,0x819E,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x019A,0x0198,0x019C,
+	0x819D,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x019A,0x0195,0x019E,0x819E,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,
+	0x01A2,0x0199,0x0195,0x019E,0x819D,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A3,0x0199,0x0195,0x019E,0x819D,0xA60F,
+	0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x0199,0x0195,0x019E,0x01A0,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A3,0x0199,
+	0x0195,0x019D,0x01A0,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A3,0x019B,0x0195,0x019E,0x819D,0xA60F,0xA603,0xA5FD,
+	0xA5F7,0xA609,0x01A3,0x019B,0x0195,0x019D,0x819D,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A3,0x019B,0x0195,0x019D,
+	0x01A0,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x019A,0x0198,0x019C,0x819D,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,
+	0x01A2,0x019A,0x0197,0x019E,0x819D,0xA60F,0xA603,0xA5FD,0xA5F7,0xA609,0x01A2,0x019A,0x0197,0x019D,0x819E,0xA60F,
+	0xA603,0xA5FD,0xA5F7,0xA609,0x01A3,0x019A,0x0195,0x81A0,0x819D,0xA60F,0xA603,0xA5FD,0xA609,0xA5F7
+};
+const uint16_t boss_gorilla_spr_tbl[] = {
+	0x01A2,0x0199,0xE9F8,0x01A2,0x019A,0xEBFB,0x01A2,0x019B,0xE8F6,0x01A1,0x0199,0xDBF6,0x01A1,0x019A,0xDD01,0x01A1,
+	0x019B,0xDAF3,0x01A3,0x0199,0xF0ED,0x01A3,0x019A,0xF2F0,0x01A3,0x019B,0xF0EB,0x0199,0x0195,0xE8FF,0x019A,0x0195,
+	0xEAFB,0x019B,0x0195,0xF7F8,0x0199,0x0196,0xE8FF,0x019A,0x0196,0xEAFB,0x019B,0x0196,0xF7F8,0x0199,0x0197,0xE8FF,
+	0x019A,0x0197,0xEAFB,0x019B,0x0197,0xF7F8,0x0199,0x0198,0xE8FF,0x019A,0x0198,0xEAFB,0x019B,0x0198,0xF7F8,0x0199,
+	0x8198,0xE8FF,0x019A,0x8198,0xEAFB,0x019B,0x8198,0xF7F8,0x0199,0x019C,0xECE2,0x0199,0x019D,0xF1DD,0x0199,0x019E,
+	0xE9D6,0x0199,0x019F,0x0CE8,0x019A,0x019C,0xECE2,0x019A,0x019D,0xF1E0,0x019A,0x019E,0xEAD4,0x019A,0x019F,0x0FEA,
+	0x019B,0x019C,0xF8DE,0x019B,0x019D,0x02DC,0x019B,0x019E,0xFBCE,0x019B,0x019F,0x1DE6,0x0199,0x819D,0xEB21,0x0199,
+	0x819E,0xE42C,0x0199,0x01A0,0x1012,0x019A,0x819D,0xEE18,0x019A,0x819E,0xEA29,0x019A,0x01A0,0x1309,0x019B,0x819D,
+	0xF91A,0x019B,0x819E,0xF329,0x019B,0x01A0,0x1E0C,0x019A,0x81A0,0x16EC
 };