Similarly to the Chaingun, BFG 9000 and newcomer Machine Gun, the Plasma Gun discards the game ammo HUD because it has its own ammunition counter in a small monitor located at the rear upper end of the weapon itself. Ammunition comes in the form of Plasma Cells, which appear to be bulky bottles that glow a luminescent blue and possess a blue-colored tip. Stray plasma bottles hold 25 units of projectile, whereas a box of 2 bottles holds double the amount. Ammunition for this weapon are generally easier to locate throughout the entire game relative to Rockets, Ammo Belts, and BFG Cells, and are particularly abundant in the EnPro facility.