diff --git a/wadsrc/decorate/doom/keen.txt b/wadsrc/decorate/doom/keen.txt
index ad1b716c9..fef060435 100644
--- a/wadsrc/decorate/doom/keen.txt
+++ b/wadsrc/decorate/doom/keen.txt
@@ -17,6 +17,7 @@ ACTOR CommanderKeen 72
 	+SHOOTABLE 
 	+COUNTKILL 
 	+NOICEDEATH
+	+ISMONSTER
 	PainSound "keen/pain"
 	DeathSound "keen/death"
 	States