The Hologram is a hand held device that, when thrown, will display a hologram of Doomguy armed with a Plasma gun to distract enemies. However, whilst the hologram can fire the weapon to further illustrate its illusion, the weapon cannot damage enemies. It is first acquired in the level Argent Energy Tower. It is an equipment item, and recharges after use.
The Hologram is also usable in multiplayer in an attempt to fool enemy players. The hologram here functions slightly different from its singleplayer counterpart, as it will first run forward when activated while firing its weapon (still doing no actual damage, only being for aesthetics); it can then be controlled to stop running and stand still.