D.E.V. is a robotic Hyena who serves Desmond as a Destructive Ellimination valor, which means his main job is to fight and capture whoever Desmond sends him after. Like all D.E.V. units, he is voice-activated, so Desmond must say "Elliminate" in order for him to attack the target.

D.E.V. Is Desmond's first, and main robot. When he was first being built, Desmond would test D.E.V.'s fighting skills on his own son, Samuel (Scourge). D.E.V.'s AI does remember Scourge, so he immediately sees him as a target.