Delta Labs - Level 4: Union Aerospace Research Division

"Your Hell awaits!"

- Malcolm Betruger

Delta Labs - Level 4: Union Aerospace Research Division is the nineteenth level of Doom 3. The player reaches the most damaged area in the base, where the invasion ultimately started. Hell knights are introduced in the cutscene.

Summary
The level begins with Betruger taunting the marine, gloating that the Soul Cube is in Hell and will never be found. The marine enters Delta Level 4, and finds bloody skeletons littering the hallways. Worse, demoralizing messages have been written on the walls in blood.

The marine finds the Main Portal in Delta, encountering only a couple of chainsaw zombies along the way. Betruger is waiting in the control room above. He activates the portal and summons a pair of Hell knights who are chasing a scientist in a biohazard suit. The Hell knights kill the scientist and then turn their attention to the marine.

The marine battles and kills both Hell knights. However, the Portal's energies expand and suck the marine into it, transporting him to Hell.

Characters

 * Malcolm Betruger
 * Unnamed scientist

PDAs

 * Jack Gilbert. Found in Delta4 Junction 2, near a locked door in a pile of skeletons.

Enemies
This map has the same enemy count on all skill levels. There are no differences in BFG Edition. * Both Hell knights have 1400 health instead of the regular 900.

Items
This map has the same item count on all skill levels. There are no differences in BFG Edition. There is also one health station on the level, with 100 health.

Starting inventory
If the player starts the level via a console command, they will start with these items:

Locker codes
For the sources of the codes, see Doom 3 locker codes.
 * Storage locker #104 - Security: 579. Contains: security armor, ammo belt, rockets (small).

Trivia

 * Rather infamously, one of the chainsaw zombies on the level wears a party cone.
 * In Delta4 Main Ready Room, in one of the corners, the words "You laugh, it works" are written in blood, amongst other writing. Finding (getting close to) this particular line grants an achievement in the BFG Edition with the same title.
 * The ending cutscene briefly shows footage of this level as Recon Zulu provides a visual status on how much damage the base has sustained from the invasion.