diff --git a/creature.go b/creature.go
index 6dcf1c1..ce58b6b 100644
--- a/creature.go
+++ b/creature.go
@@ -169,7 +169,9 @@ func (machine *Machine) Execute(offset int) {
 			}
 			function, exists := machine.functions[id]
 			if exists {
-				function(machine)
+				if function(machine) {
+					return
+				}
 			}
 		}
 		machine.counter++