One of the most effective methods of combating the large, armored Hunters in the Marathon series was the Zeus fusion pistol. Remarkably similar to the plasma pistol in Halo, it had an alt-fire mode that charged up over time and fired one powerful projectile. This depleted the weapon quickly, but a few such blasts could take out a Hunter quickly. Interestingly, like a phaser in "Star Trek", if the alt-fire was held down too long, the weapon would explode and kill the user. An audible alarm beeps as you charge the weapon, faster and faster, until detonation. The plasma pistol in Halo doesn't seem to have this "feature". Also, unlike its counterparts in Halo, the fusion pistol's alt-fire projectiles are not guided.