diff --git a/src/p_floor.c b/src/p_floor.c
index cde657a18..01ae011ed 100644
--- a/src/p_floor.c
+++ b/src/p_floor.c
@@ -2947,7 +2947,7 @@ void EV_CrumbleChain(sector_t *sec, ffloor_t *rover)
 					spawned = P_SpawnMobj(a, b, c, type);
 
 					if (spawned->frame & FF_ANIMATE)
-						spawned->frame += P_RandomKey(spawned->state->var2);
+						spawned->frame += P_RandomKey(spawned->state->var1);
 
 					spawned->angle += P_RandomKey(36)*ANG10; // irrelevant for default objects but might make sense for some custom ones