The weapon of choice for the elite soldiers aboard the UESC Marathon, the Tech .50 Fusion Pistol is the third weapon found by the Security Officer in the first Marathon game. Effective against flesh and cybernetics alike, this vacuum enabled weapon was an invaluable tool during the Security Officer's efforts in defending the Marathon itself, and launching offensive maneuvers onto the Pfhor scoutship Sfiera.
The Tech .50 Fusion Pistol is powered by a Deuterioxide Halogen Battery Pack, capable of producing 116.6 terawatts of power. Each battery is capable of firing 20 high impact energy bolts, each one with a yield of 5.83 terawatts. It can be fired in vacuum.
The weapon is also capable of an overcharge, during which the internal MicroFuse Reaction Core fires one large energy bolt with a yield of 17.5 terawatts.
The fusion pistol does not deal bonus damage against mechanical enemies in Marathon (1994). However, it is still a valuable tool for the player character.
The overcharge is not dependent on the amount of charge left in the battery, so the fusion pistol can shoot an overcharge shot even at 1% battery charge.
- The Fusion Pistol's bonus damage against cybernetic enemies would only be implemented in the sequels.
- The terminal in Marathon (1994) calls the weapon the 'Zeus-Class Fusion Pistol', but the manual calls it the 'Tech .50 Fusion Pistol'. The name would go on to be used in the sequels.
- The output of the Fusion Pistol is 5.83 x 1012 watts! For reference, New York City uses 50.6 Terawatt hours in a year.