Those G.U.N troopers are humanoid-like robots made from a very solid iron.
GUN Troopers have good resistance to damage. When facing them, it takes about four Homing Attacks to destroy them. However they are not as strong as the Big Foots. The GUN Troopers also wield weapons like RPGs, Semi-Auto Rifles and Bazookas which they will use against the playable character. Once a GUN Trooper is defeated, it will drop its weapon, allowing the playable character to use it themselves. They each also grant 250 Dark points upon defeat.