diff --git a/zspecial.acs b/zspecial.acs
index 793f9fc..6668464 100644
--- a/zspecial.acs
+++ b/zspecial.acs
@@ -243,6 +243,7 @@ special
 	-24:SetUserVariable(3),
 	-25:GetUserVariable(2),
 	-26:Radius_Quake2(6),
+	-27:CheckActorClass(2),
 
 	-1000:__EndOfList__(10);