Central Processing: Primary Server Bank

CENTRAL PROCESSING - "Central Processing houses the control systems which are used to process data for experiments, archive data, and manage the CPU overhead for security and regular day-to-day operations of the entire outpost on Mars."

Central Processing: Primary Server Bank is the twenty-third level of Doom 3. The player fights a boss, Sabaoth, which is a transformed Sergeant Kelly. Sabaoth has integrated Campbell's BFG into his cybernetic tank-body, and uses it against the player. After defeating Sabaoth, the player acquires Campbell's BFG.

Walkthrough
This level is more based on intense fights than the previous ones. You are in some sort of "Q" shapped room, in the queue. Then, you have to chose right or left. If you walk a few steps to the left, it will cause two doors to open on the far left, releasing an Imp and a Chaingun Commando, and a third door on the far right, releasing a second Imp. Additionally, some Trites will come from both sides. If you walk a few steps to the right, it will cause two doors to open on the far left, releasing a Revenant and a Chaingun Commando, and a third door on the far right, releasing a second Revenant. Additionally, some Trites will come from both sides, once again. Both sides then connect to a spacious room, with some data servers at its center. There are an Armor, a Medkit, an Adrenaline Boost, a Grenades pack and an Ammo Belt on one of the sides of the room, and another Medkit, a Shell Box, another Ammo Belt and a door in the other side. If you go toward the Adrenaline Boost side, two caches will open from both sides of the pick ups, revealing a Revenant and an Arch-vile. If you approach the door, an Arch-vile will appear before, and an Imp will appear between the server banks. Both Arch-viles summon Wraiths while they are alive.

Make sure to kill everything in the room before taking all items including the ones in the first half of the level : a Rocket Launcher, an Armor, an Adrenaline Boost, a Medkit, a Cell pack, a Clip, a Grenades pack. Then pass the door.

The door leads to a gigantic room where you call a rotating bridge. As you walk in, 3 Cacodemons will appear, a pair after killing a lone one. Kill them and proceed to the central pillar. You'll have to choose your destination.

Storage

This is purely optional, but offers great rewards. You enter in a corridor. For the moment, ready you Chainsaw, ignore the door on your left and walk a bit to the right; you'll face 3 Tentacle Commandos coming from front. Then enter to the door from where came the Commandos. You'll see a BFG Cell glowing (with a Stimpack). As you take the Stimpack, the wall in front of it lowers and reveal a Revenant at immediate vicinity. Kill him. Then take the bottom door in the room, kill the Revenant there is behind, and turn back: a third and last Arch-vile teleports behind you, summoning Wraiths as usual. If you completed the "Servers" section first, you'll then have to manage the Cube fueling, to make sure it will be ready for the end of the level; then, if it is ready, use it for the Arch-vile (or keep it until the last fight). You'll have to kill at least one Wraith to later complete the 5 victims needed until the last part. Replenish your ammunitions in the room where you killed the Revenant (5 Cell packs, a Plasma Gun, 2 Ammo Belts, 2 Clips, a Large Rockets box, an Armor and a Shell Box). On the backtrack, a third and last Arch-vile will teleport in, summoning Wraiths as usual. Backtrack and note the door you didn't take at first (at your left when you entered the corridor); there are an explosive barrel and 2 Ammo Belts behind, but an Imp teleports in behind you. Finally, another Cacodemon has spawned at the bridge.

Servers

You have to do this one before the Central Processing. You arrive in a curvy hallway. Walk a bit and a duo of Imps will teleport before you, on each side of the door. The desk on the left houses a Clip and a Large Rocket Box. Cross the door, and notice the dark room on the left. An Imp waits here. Kill him, walk a bit, and be prepared as you approach the next door: another Imp will teleport behind and the Tentacle Commando below will run towards you from this door. Kill them and cross the door the Commando came from. You'll hear Trites coming in this pitch black room. Kill them, go down a few steps, and make a stop. You'll hear an Imp teleporting on your right. Then, take the right side, take the Clip and Shell Box here, kill the additional 2 Trites who spawned, then take the path where the Imp teleported, walk a bit on the darkness, kill the Imp in the (already open) red niche on the right (there is also a Medkit here), then pass the door. You are in a well-lit room, actually in the previous room but at floor level. Two Imps will teleport: one in your left, and the other behind the computer shelves. From here, either keep the Soul Cube or imperatively use it on the first Imp, in order to be sure the final enemies of the level will fuel it for the final battle. However, if you haven't completed the Storage section and you want to do it, you are free to use the Cube when you want. Then, take the 2 Cell packs, the 2 Clips, the PDA and the Medkit, and backtrack. There is nothing in the pitch black room, but another "front and behind Imps duo" will teleport in, where you faced the Tentacle Commandos. Once all is clear, you can jump from the window in front of the door leading to the Trites room, to reclaim the Rocket Box, Ammo Belt and Large Cell pack you can see below. Then return to the central pillar. Beware, another pair of Cacodemons will spawn.

Central Processing

You have to collect the PDA in the "Servers" section to select it. The bridge will leads you to the final room of the level, not without spawning a last pair of Cacodemons. Then walk in the hallway, take all you can here, including the BFG 9000 Videodisk, the 2 Ammo Belts, the 2 Medkits, the Large Rockets Box, and enter the final room, finally facing Sergeant Kelly. You might save before, as if you die against him, you'll have to restart the entire level.

The best bet to kill Kelly, now transformed into Sabaoth, is to douse him with Machine Gun or Chain Gun ; the hitscan shots will destroy his BFG shots rather quickly and easily. Note that the first two BFG shots, you can use the Rocket Launcher, as Sabaoth's trajectories are the same that ones of his shots. Once you are low on health (don't wait too long), unleash the Soul Cube. Once Sabaoth is dead, pick his BFG 9000, crawl through an open-end vent which leads to an underground structure, where you just have to take a Clip, a Shell Box, some Armor Shards and the elevator to the exit.

PDAs

 * Steve Tooloose

Video Disks

 * BFG 9000 Briefing

Characters

 * Thomas Kelly/Sabaoth

Enemies

 * Sabaoth (boss)
 * 14 Imps
 * 4 Commandos
 * 2 Chaingun Commandos
 * 5 Revenants
 * Trites
 * 3 Arch-viles
 * Wraiths
 * 6 Cacodemons

Weapons/Items

 * Grenades
 * Chainguns
 * Plasma Guns
 * BFG-9000
 * Medkits
 * Security Armor
 * Armor Shards
 * Bullets
 * Shells
 * Clips
 * Ammo Belts
 * Plasma Cells
 * Rockets
 * BFG Cell

Cabinet Codes
None