diff --git a/src/Bullet.cpp b/src/Bullet.cpp
index f3a95bb3..fde280c0 100644
--- a/src/Bullet.cpp
+++ b/src/Bullet.cpp
@@ -1643,7 +1643,9 @@ void ActBullet_Edge(BULLET *bul)
 			if (bul->ani_no > 4)
 			{
 				bul->cond = 0;
-				return;	// Prevent UB at rc[bul->ani_no] when bul->ani_no == 5
+			#ifdef FIX_BUGS
+				return;	// The code below will use 'ani_no' to access 'rcLeft' and 'rcRight', even though it's now too high
+			#endif
 			}
 
 			break;
diff --git a/src/Caret.cpp b/src/Caret.cpp
index 5e4293f0..e34a89ec 100644
--- a/src/Caret.cpp
+++ b/src/Caret.cpp
@@ -71,10 +71,13 @@ void ActCaret01(CARET *crt)
 	if (++crt->ani_wait > 5)
 	{
 		crt->ani_wait = 0;
+
 		if (++crt->ani_no > 3)
 		{
 			crt->cond = 0;
-			return;	// Prevent UB at rc[crt->ani_no] when crt->ani_no == 4
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rcLeft' and 'rcRight', even though it's now too high
+		#endif
 		}
 	}
 
@@ -121,7 +124,9 @@ void ActCaret02(CARET *crt)
 			if (crt->ani_no > 3)
 			{
 				crt->cond = 0;
-				return;	// Avoid unconditional UB at rect_left[crt->ani_no]
+			#ifdef FIX_BUGS
+				return;	// The code below will use 'ani_no' to access 'rect_left', even though it's now too high
+			#endif
 			}
 
 			crt->rect = rect_left[crt->ani_no];
@@ -137,7 +142,9 @@ void ActCaret02(CARET *crt)
 			if (crt->ani_no > 3)
 			{
 				crt->cond = 0;
-				return;	// Avoid unconditional UB at rect_right[crt->ani_no]
+			#ifdef FIX_BUGS
+				return;	// The code below will use 'ani_no' to access 'rect_right', even though it's now too high
+			#endif
 			}
 
 			crt->rect = rect_right[crt->ani_no];
@@ -165,10 +172,13 @@ void ActCaret03(CARET *crt)
 	if (++crt->ani_wait > 2)
 	{
 		crt->ani_wait = 0;
+
 		if (++crt->ani_no > 3)
 		{
 			crt->cond = 0;
-			return;	// Return now, or the access to rect[crt->ani_no] we do is UB
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rect', even though it's now too high
+		#endif
 		}
 	}
 
@@ -181,9 +191,11 @@ void ActCaret04(CARET *crt)
 		{64, 32, 80, 48},
 		{80, 32, 96, 48},
 		{96, 32, 112, 48},
+
 		{64, 48, 80, 64},
 		{80, 48, 96, 64},
 		{96, 48, 112, 64},
+
 		{64, 64, 80, 80},
 		{80, 64, 96, 80},
 		{96, 64, 112, 80},
@@ -194,7 +206,12 @@ void ActCaret04(CARET *crt)
 		crt->ani_wait = 0;
 
 		if (++crt->ani_no > 2)
+		{
 			crt->cond = 0;
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rect', even though it's now too high
+		#endif
+		}
 	}
 
 	crt->rect = rect[(crt->direct * 3) + crt->ani_no];
@@ -218,15 +235,17 @@ void ActCaret05(CARET *crt)
 		++crt->ani_no;
 	}
 
-	crt->x += 0x80;
-	crt->y -= 0x80;
-
 	if (crt->ani_no > 6)
 	{
 		crt->cond = 0;
-		return;	// Return now, or the access to rect[crt->ani_no] we do is UB
+	#ifdef FIX_BUGS
+		return;	// The code below will use 'ani_no' to access 'rect', even though it's now too high
+	#endif
 	}
 
+	crt->x += 0x80;
+	crt->y -= 0x80;
+
 	crt->rect = rect[crt->ani_no];
 }
 
@@ -249,7 +268,9 @@ void ActCaret07(CARET *crt)
 		if (++crt->ani_no > 6)
 		{
 			crt->cond = 0;
-			return;	// Prevent UB at rcLeft[crt->ani_no] when crt->ani_no == 6
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rcLeft', even though it's now too high
+		#endif
 		}
 	}
 
@@ -365,10 +386,13 @@ void ActCaret11(CARET *crt)
 	if (++crt->ani_wait > 2)
 	{
 		crt->ani_wait = 0;
+
 		if (++crt->ani_no > 6)
 		{
 			crt->cond = 0;
-			return;	// Avoid unconditional UB at rcRight[crt->ani_no]
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rcRight', even though it's now too high
+		#endif
 		}
 	}
 
@@ -385,10 +409,13 @@ void ActCaret12(CARET *crt)
 	if (++crt->ani_wait > 2)
 	{
 		crt->ani_wait = 0;
+
 		if (++crt->ani_no > 1)
 		{
 			crt->cond = 0;
-			return;	// Return now, or the access to rcLeft[crt->ani_no] we do is UB
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rcLeft', even though it's now too high
+		#endif
 		}
 	}
 
@@ -456,7 +483,9 @@ void ActCaret14(CARET *crt)
 		if (++crt->ani_no > 4)
 		{
 			crt->cond = 0;
-			return;	// Prevent UB at rect[crt->ani_no] when crt->ani_no == 5
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rect', even though it's now too high
+		#endif
 		}
 	}
 
@@ -479,7 +508,9 @@ void ActCaret15(CARET *crt)
 		if (++crt->ani_no > 3)
 		{
 			crt->cond = 0;
-			return;	// Prevent UB at rcLeft[crt->ani_no] when crt->ani_no == 4
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rcLeft', even though it's now too high
+		#endif
 		}
 	}
 
diff --git a/src/MycParam.cpp b/src/MycParam.cpp
index 318630d6..4ccf7180 100644
--- a/src/MycParam.cpp
+++ b/src/MycParam.cpp
@@ -273,8 +273,14 @@ void PutArmsEnergy(BOOL flash)
 	RECT rcExpFlash = {40, 80, 80, 88};
 
 	int lv = gArmsData[gSelectedArms].level - 1;
-	if (lv < 0)	// Detect the case where the level is 0 (no weapon)
-		lv = 0;	// Set lv to a safe value
+
+#ifdef FIX_BUGS
+	// When the player has no weapons, the default level is 0, which becomes -1.
+	// Catch it, and set it to 0 instead, so the following array-accesses aren't
+	// out-of-bounds.
+	if (lv < 0)
+		lv = 0;
+#endif
 
 	int arms_code = gArmsData[gSelectedArms].code;
 	int exp_now = gArmsData[gSelectedArms].exp;
diff --git a/src/NpcAct120.cpp b/src/NpcAct120.cpp
index 5bfc1eb0..801cbf0b 100644
--- a/src/NpcAct120.cpp
+++ b/src/NpcAct120.cpp
@@ -585,10 +585,13 @@ void ActNpc127(NPCHAR *npc)
 	if (++npc->ani_wait > 0)
 	{
 		npc->ani_wait = 0;
+
 		if (++npc->ani_no > 2)
 		{
 			npc->cond = 0;
-			return; // Prevent UB at rc[npc->ani_no] when npc->ani_no == 3
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rcH' and 'rcV', even though it's now too high
+		#endif
 		}
 	}
 
@@ -652,7 +655,9 @@ void ActNpc128(NPCHAR *npc)
 	if (++npc->ani_no > 4)
 	{
 		npc->cond = 0;
-		return;	// Prevent UB at rc[npc->ani_no] when npc->ani_no == 5
+	#ifdef FIX_BUGS
+		return;	// The code below will use 'ani_no' to access 'rcLeft' and co., even though it's now too high
+	#endif
 	}
 
 	switch (npc->direct)
@@ -682,18 +687,23 @@ void ActNpc129(NPCHAR *npc)
 		{0x80, 0x30, 0x90, 0x40},
 		{0x90, 0x30, 0xA0, 0x40},
 		{0xA0, 0x30, 0xB0, 0x40},
+
 		{0x80, 0x40, 0x90, 0x50},
 		{0x90, 0x40, 0xA0, 0x50},
 		{0xA0, 0x40, 0xB0, 0x50},
+
 		{0x80, 0x50, 0x90, 0x60},
 		{0x90, 0x50, 0xA0, 0x60},
 		{0xA0, 0x50, 0xB0, 0x60},
+
 		{0xB0, 0x30, 0xC0, 0x40},
 		{0xC0, 0x30, 0xD0, 0x40},
 		{0xD0, 0x30, 0xE0, 0x40},
+
 		{0xB0, 0x40, 0xC0, 0x50},
 		{0xC0, 0x40, 0xD0, 0x50},
 		{0xD0, 0x40, 0xE0, 0x50},
+
 		{0xB0, 0x50, 0xC0, 0x60},
 		{0xC0, 0x50, 0xD0, 0x60},
 		{0xD0, 0x50, 0xE0, 0x60},
@@ -706,7 +716,9 @@ void ActNpc129(NPCHAR *npc)
 		if (++npc->ani_no > 2)
 		{
 			npc->cond = 0;
-			return;	// Prevent UB at rect[(npc->direct * 3) + npc->ani_no] when npc->direct == 5 and npc->ani_no == 3
+		#ifdef FIX_BUGS
+			return;	// The code below will use 'ani_no' to access 'rect', even though it's now too high
+		#endif
 		}
 	}
 
diff --git a/src/NpcAct140.cpp b/src/NpcAct140.cpp
index 4d718f57..1aae6938 100644
--- a/src/NpcAct140.cpp
+++ b/src/NpcAct140.cpp
@@ -753,7 +753,9 @@ void ActNpc146(NPCHAR *npc)
 			{
 				SetDestroyNpChar(npc->x, npc->y, 0x1000, 8);
 				npc->cond = 0;
-				return;	// Prevent UB at rect[npc->ani_no] when npc->ani_no == 5
+			#ifdef FIX_BUGS
+				return;	// The code below will use 'ani_no' to access 'rect', even though it's now too high
+			#endif
 			}
 
 			break;
diff --git a/src/NpcAct180.cpp b/src/NpcAct180.cpp
index 76f27294..cfb426ab 100644
--- a/src/NpcAct180.cpp
+++ b/src/NpcAct180.cpp
@@ -1428,7 +1428,9 @@ void ActNpc199(NPCHAR *npc)
 	if (npc->ani_no > 4)
 	{
 		npc->cond = 0;
-		return;	// Prevent UB at rect[npc->ani_no] when npc->ani_no == 5
+	#ifdef FIX_BUGS
+		return;	// The code below will use 'ani_no' to access 'rect', even though it's now too high
+	#endif
 	}
 
 	npc->x += npc->xm;