diff --git a/src/monster.c b/src/monster.c
index 6cc416f..90cab32 100644
--- a/src/monster.c
+++ b/src/monster.c
@@ -128,7 +128,12 @@ damage_surroundings(Monster *m, RoomMatrix *rm)
 		for (Sint32 j = -1; j <= 1; ++j) {
 			if (i == 0 && j == 0)
 				continue;
-			RoomSpace *r = &rm->spaces[roomPos.x + i][roomPos.y + j];
+
+			Position matrixPos = POS(roomPos.x + i, roomPos.y + j);
+			if (!position_in_roommatrix(&matrixPos))
+				continue;
+
+			RoomSpace *r = &rm->spaces[matrixPos.x][matrixPos.y];
 			if (r->monster) {
 				int dmg = stats_fight(&m->stats, &r->monster->stats);
 				monster_hit(r->monster, dmg);
diff --git a/src/skill.c b/src/skill.c
index e1d012e..6923b0e 100644
--- a/src/skill.c
+++ b/src/skill.c
@@ -879,7 +879,11 @@ skill_erupt(Skill *skill, SkillData *data)
 			if (i == 0 && j == 0)
 				continue;
 
-			RoomSpace *r = &rm->spaces[playerMPos.x + i][playerMPos.y + j];
+			Position matrixPos = POS(playerMPos.x + i, playerMPos.y + j);
+			if (!position_in_roommatrix(&matrixPos))
+				continue;
+
+			RoomSpace *r = &rm->spaces[matrixPos.x][matrixPos.y];
 			if (r->monster) {
 				player->stats.advantage = true;
 				int dmg = stats_fight(&player->stats, &r->monster->stats);