The smart ones will either attack all players, or none. The others won't attack players at all. I can't imagine a iron golem guardian would much of a match for a player with semi-decent gear. The way to do what I think you want to do is MFFS, give admitted players permissions and it will kill the rest. It can even disarm them, pick up the loot when they get killed, and spit on their corpse(ok I made that last part up).
I just made X - Dynamics ( Ripoff much? ) and got the idea from POI to make a secret floor with a machine that spies on people and i want to make it more lively with golems posing as guards, scientists etc .