Bio-suit zombie

The Bio-Suit Zombie, also known as a Hazmat Zombie, is a monster included in Doom 3: Resurrection of Evil (RoE).

The Bio-suit Zombie, normally found in toxic areas where there is no oxygen, wears a yellow Hazmat suit. They behave very much like normal zombies, slashing at nearby players. When killed, they drop valuable air tanks, which help the player stay alive much longer in toxic areas. The Hazmat Zombie is not found very often in the game.

Earlier Version
Screenshots released early in the development of RoE depict the Bio-Suit Zombie as wearing a dark-grey Hazmat suit that has a red band just below each elbow. Besides these two main differences, several similarities between this earlier version & the retail version of the monster remains. It is not clear if this earlier version of the monster was meant to be the final version of the monster or if the version was merely a stand-in until a later design could be finalized.

Links
Screenshot of early version of the Bio-Suit Zombie (appears on left)