Delta Labs (Doom Resurrection)

Delta Labs is the fourth level of Doom Resurrection. It is an area of the Delta Labs location. The player finds more information, and Dr. Garrett informs him that a colleague of his, Dr. Martin, is hiding nearby. When Dr. Martin is found, he mentions that a monster bit him earlier but he tells the player that the UAC has opened a gateway to Hell. After granting his credentials to activate the tram controls and shut down the teleporters to Sam, Dr. Martin dies, transforming into a zombie. The player brings the tram online, but Dr. Garrett is attacked and seems to be in trouble. The marine himself is attacked at the teleporter by a Hell knight and is thrown through the portal into Hell.

The chaingun is introduced as a weapon, and the maggot and chaingun commando first appear as enemies.

Essentials
The Hell knight is fought in a boss battle and has a visible life bar. When its HP is depleted, it grabs the player and tosses him into the portal, sending him into Hell.