diff --git a/src/dehacked.c b/src/dehacked.c
index 155e2b5ce..baa5f13b3 100644
--- a/src/dehacked.c
+++ b/src/dehacked.c
@@ -2228,6 +2228,7 @@ static actionpointer_t actionpointers[] =
 	{{A_DoNPCPain},              "A_DONPCPAIN"},
 	{{A_Boss5ExtraRepeat},       "A_BOSS5EXTRAREPEAT"},
 	{{A_Boss5CheckOnGround},     "A_BOSS5CHECKONGROUND"},
+	{{A_Boss5CheckFalling},      "A_BOSS5CHECKFALLING"},
 
 	{{NULL},                   "NONE"},
 
diff --git a/src/info.h b/src/info.h
index f623aaa1f..166402651 100644
--- a/src/info.h
+++ b/src/info.h
@@ -242,6 +242,7 @@ void A_CheckFlags2();
 void A_DoNPCPain();
 void A_Boss5ExtraRepeat();
 void A_Boss5CheckOnGround();
+void A_Boss5CheckFalling();
 
 // ratio of states to sprites to mobj types is roughly 6 : 1 : 1
 #define NUMMOBJFREESLOTS 256
diff --git a/src/p_enemy.c b/src/p_enemy.c
index 0746f629f..118367da4 100644
--- a/src/p_enemy.c
+++ b/src/p_enemy.c
@@ -268,6 +268,7 @@ void A_CryingToMomma(mobj_t *actor);
 void A_CheckFlags2(mobj_t *actor);
 void A_DoNPCPain(mobj_t *actor);
 void A_Boss5CheckOnGround(mobj_t *actor);
+void A_Boss5CheckFalling(mobj_t *actor);
 //for p_enemy.c
 
 //
@@ -11982,3 +11983,31 @@ void A_Boss5CheckOnGround(mobj_t *actor)
 		actor->momy = (4*actor->momy)/5;
 	}
 }
+
+// Function: A_Boss5CheckFalling
+//
+// Description: Falling checker.
+//
+// var1 = state to change to when hitting ground.
+// var2 = state to change to when falling.
+//
+void A_Boss5CheckFalling(mobj_t *actor)
+{
+	INT32 locvar1 = var1;
+	INT32 locvar2 = var2;
+#ifdef HAVE_BLUA
+	if (LUA_CallAction("A_Boss5CheckFalling", actor))
+		return;
+#endif
+
+	if (actor->health && actor->extravalue2 > 1)
+	{
+		var1 = locvar1;
+		var2 = 0;
+		A_Boss5CheckOnGround(actor);
+		return;
+	}
+
+	if (P_MobjFlip(actor)*actor->momz <= 0)
+		P_SetMobjState(actor, locvar2);
+}