diff --git a/src/playsim/actor.h b/src/playsim/actor.h
index 583050bb569..2f461e10897 100644
--- a/src/playsim/actor.h
+++ b/src/playsim/actor.h
@@ -891,7 +891,7 @@ class AActor final : public DThinker
 	// Called when bouncing to allow for custom behavior.
 	// Returns -1 for normal behavior, 0 to stop, and 1 to keep going.
 	// (virtual on the script side only)
-	int SpecialBounceHit(AActor* bounceMobj, line_t* bounceLine, secplane_t* bouncePlane);
+	int SpecialBounceHit(AActor* bounceMobj, line_t* bounceLine, secplane_t* bouncePlane, bool is3DFloor);
 
 	// Returns true if it's okay to switch target to "other" after being attacked by it.
 	bool CallOkayToSwitchTarget(AActor *other);
diff --git a/src/playsim/p_map.cpp b/src/playsim/p_map.cpp
index 04ffa12c062..949514f2a77 100644
--- a/src/playsim/p_map.cpp
+++ b/src/playsim/p_map.cpp
@@ -3608,7 +3608,7 @@ bool FSlide::BounceWall(AActor *mo)
 
 	if (mo->flags & MF_MISSILE)
 	{
-		switch (mo->SpecialBounceHit(nullptr, line, nullptr))
+		switch (mo->SpecialBounceHit(nullptr, line, nullptr, false))
 		{
 			case 1:		return true;
 			case 0:		return false;
@@ -3708,7 +3708,7 @@ bool P_BounceActor(AActor *mo, AActor *BlockingMobj, bool ontop)
 			default:	break;
 		}
 
-		switch (mo->SpecialBounceHit(BlockingMobj, nullptr, nullptr))
+		switch (mo->SpecialBounceHit(BlockingMobj, nullptr, nullptr, false))
 		{
 			case 1:		return true;
 			case 0:		return false;
diff --git a/src/playsim/p_mobj.cpp b/src/playsim/p_mobj.cpp
index 1552ed9f542..9700118504a 100644
--- a/src/playsim/p_mobj.cpp
+++ b/src/playsim/p_mobj.cpp
@@ -1743,7 +1743,7 @@ bool AActor::FloorBounceMissile (secplane_t &plane, bool is3DFloor)
 {
 	if (flags & MF_MISSILE)
 	{
-		switch (SpecialBounceHit(nullptr, nullptr, &plane))
+		switch (SpecialBounceHit(nullptr, nullptr, &plane, is3DFloor))
 		{
 			// This one is backwards for some reason...
 			case 1:		return false;
@@ -3420,15 +3420,15 @@ int AActor::SpecialMissileHit (AActor *victim)
 }
 
 // This virtual method only exists on the script side.
-int AActor::SpecialBounceHit(AActor* bounceMobj, line_t* bounceLine, secplane_t* bouncePlane)
+int AActor::SpecialBounceHit(AActor* bounceMobj, line_t* bounceLine, secplane_t* bouncePlane, bool is3DFloor)
 {
 	IFVIRTUAL(AActor, SpecialBounceHit)
 	{
-		VMValue params[4] = { (DObject*)this, bounceMobj, bounceLine, bouncePlane };
+		VMValue params[] = { (DObject*)this, bounceMobj, bounceLine, bouncePlane, is3DFloor };
 		VMReturn ret;
 		int retval;
 		ret.IntAt(&retval);
-		VMCall(func, params, 4, &ret, 1);
+		VMCall(func, params, 5, &ret, 1);
 		return retval;
 	}
 	else return -1;
diff --git a/wadsrc/static/zscript/actors/actor.zs b/wadsrc/static/zscript/actors/actor.zs
index 0893c107f24..a809e674d9c 100644
--- a/wadsrc/static/zscript/actors/actor.zs
+++ b/wadsrc/static/zscript/actors/actor.zs
@@ -581,7 +581,7 @@ class Actor : Thinker native
 	}
 
 	// This is called when a missile bounces off something.
-	virtual int SpecialBounceHit(Actor bounceMobj, Line bounceLine, readonly<SecPlane> bouncePlane)
+	virtual int SpecialBounceHit(Actor bounceMobj, Line bounceLine, readonly<SecPlane> bouncePlane, bool is3DFloor = false)
 	{
 		return MHIT_DEFAULT;
 	}