The resemblance is most apparent when the player lifts the weapon at the end of a volley. The designers simply turned the detachment around so that it was shown backwards.
The area in front of the bipod could be detached to use as a separate weapon. The links show a dart-shooting, M60-like toy that was popular in the early 1990s (back then, it was tan). For the release of Doom, these plasma bursts were made blue-white, and the gun sprite was changed slightly. This is similar to that version's BFG9000, which fires 40 of the same projectiles per shot.
In the Doom press release beta, the plasma gun fires green-white and orange-red bursts, alternating between the two colors.It shares the player's stock of cells with the BFG9000 as a source of ammo. The Plasma Gun (also known as the Plasma Rifle in the game manuals and help screen) is a futuristic weapon with a barrel that roughly resembles an accordion, which fires blue and white bursts of plasma. 'Plasma Rifles shoot multiple rounds of plasma energy - frying some demon butt!' The plasma gun in E4M2: Perfect Hatred appears to be unguarded.
