diff --git a/zdefs.acs b/zdefs.acs
index 407fdc8..91aae71 100644
--- a/zdefs.acs
+++ b/zdefs.acs
@@ -807,4 +807,5 @@
 #define PRINTNAME_LEVEL -2
 #define PRINTNAME_SKILL -3
 
-
+#define CSF_NOFAKEFLOORS 1
+#define CSF_NOBLOCKALL 2
diff --git a/zspecial.acs b/zspecial.acs
index 68d1794..3ea4ef9 100644
--- a/zspecial.acs
+++ b/zspecial.acs
@@ -273,6 +273,7 @@ special
 	-32:SoundSequenceOnPolyobj(2),
 	-33:GetPolyobjX(1),
 	-34:GetPolyobjY(1),
+    -35:CheckSight(3),
 
 	-1000:__EndOfList__(10);