"This game runs perfectly on my G3 MiniTower 333mhz in Mac OS 9.2.1 but only with extensions off. Try starting your G4 up with Extensions Off. When your running Mac OS 9 normally it will just freeze up the system. Good luck! Very very fun game though. I remember I bought this game a while back, it came on a few floppies. Those are now lost or broken. I am so happy I can play that game again. :-)" - PowerBook86
"the only thing to do is turn virtual memory off! it will freeze with it turned on on macos 9!! btw try the original version - fury of the furies - better controls & no stupid pac man!" - mctom
A word about the controls: It uses the number block to move around, but to shoot you need the space bar.Compatibility
In the game's references dialog you can set game width as well as whether you want to play in 16 or 256 colors.