diff --git a/compiler limitations.md b/compiler limitations.md
index dd74345..f399d3d 100644
--- a/compiler limitations.md	
+++ b/compiler limitations.md	
@@ -62,3 +62,9 @@ level waittill( var, player );
 WILL COMPILE BUT
 ```
 The notify/waittill won't work.
+
+**9. You cannot explicitly define a variable as a boolean**
+```
+level.boolean = true;
+```
+This will compile ok but it will cause instability and crash erratically.
\ No newline at end of file