Possessed

The Possessed are a class of zombie-like monsters which appear in the Doom. They are similar to the zombies of Doom 3 in behavior and in their status as pure, unarmed cannon fodder.

Codex data
"The Possessed are created in Lazarus Wave event, a phenomenon first discovered by Dr. Olivia Pierce during her Lazarus Project. While most of victims exposed to Argent biowaves will expire without further effect, some subjects will absorb traces of Argent Energy and enter state of posthumous vigor. Despite necrosis of the internal organs (with the exception of the brain), the victim continues to animate and exhibit a low order of sentience for weeks or even months after clinical death. Posthumous brain activity in the Possessed is limited to instinctive behavior. The Possessed are known to be territorial when confronted by the living. When isolated, they will often enter a dormant state of extended periods of time. They will stand, unmoving, for days or weeks at a time until presented with a live food source, or threatened by a predator."

- Codex entry