Caverns - Area 1: Excavation Transfer

CARVERNS - AREA 1 - "Caverns Area 1 is the location of the original Mars Base. While all research has been moved to newer structures, this aging facility still serves as the primary material transfer point between Area 2 and Site 3."

Caverns - Area 1: Excavation Transfer is the twenty-fifth level of Doom 3. The player advances towards the primary excavation site, where the Hell portal is located. Level 1 contains the oldest, original Mars base. It is also the last level to have a fictional character PDA.

Walkthrough
Step out of the lift, then retreat when you hear the dozen of Trites coming at you. Once they are dead, search for a hole in the ground, housing an Armor and a Grenades pack. Climb the stairs and kill the Imp atop. On the catwalk, a traditional "front and behind duo" of Wraiths will appear. Continue until reaching the pile of crates. There is an Armor pickup behind them and an Ammo Belt nearby. If you take the Ammo Belt, four Wraiths will come from the stairs. Then, you can enter the shelter.

The shelter is composed of three tiny rooms. The first one is empty. When entering the second one, an Imp will teleport in front of you. The room contains 2 Cell Packs, 2 Clips, a Health Station, a Shells Clip and Rockets Box. As soon as you enter the third room, a pair of Wraiths will come from behind. It houses a BFG Cell. Pass the final door.

You are now in a "T" shaped tunnel. Kill the Chaingun Commando. As you walk in, four Wraiths will teleport around. Kill them and enter the tiny empty room, collecting a Shotgun in the process. Then, take the (only) door on the right.

You are in a somewhat circular room. An Arch-vile will teleport in front of you, summoning Imps and Wraiths. Beware as a couple of Chaingun Commandos will also come from behind once they are dead. Take the 2 Large Cell Packs and pass the door. From now on, if you return to the "T" tunnel, you'll face a pair of Wraiths coming from the shelter.

The next room is tiny, and houses an Imp, some Trites, a Health Station, an Armor, a Machine Gun and a Clip. Pass the door.

You are now in a large cave. The door in front of you is locked. You can go down the maintenance shaft of the main lift. Walking on the structure awards an Ammo Belt and crawling in the vent awards a Chain Gun. Climb one of the side ladders to return to the main course. Turn around the building perimeter to find the monitor which controls the ladder which permits to climb on the roof of the structure. Beware, a traditional "front and behind duo" of Cacodemons will teleport in as you reach the roof. Then, jump on the catwalk and enter the shelter through the window.

As the first shelter, this one is composed of three tiny rooms. There is a computer in the first one you have to trigger to make the main elevator switch activable in the cave. There is also a Stimpack. The second one only contains a BFG Cell, 3 Shell packs, a Clip, and a lift, leading to the fourth and last room. It houses 2 Cell Packs, a Rocket Box which will cause Trites swarming, and a door leading back to the cave (it is the previously locked one).

You can now call the main lift in the cave. As soon as you do it, the doors lock, and enemies teleports in: two Imps and a Hell Knight. Then, collect any items you can collect before activating the lift, as it forbids any return. Now the hard time begins...

You arrive in a very large cave, with a "sniping" Chaingun Commando firing at you from distance. Kill him, then proceed to the ground. The lava doesn't kill you, albeit it damages you. As you walk, an Arch-vile appears where was the Commando. Some Imps and even Hell Knights will be summoned by the Arch-vile. In addition, a Cacodemon also spawns. Destroy everyone, and activate the monitor on a pillar on the left side: it will lower a ladder on this pillar. Climb it, kill the Wraith atop, take the BFG Cell near him, and enter the shelter. Beware of the jumping Imp.

Inside, a second Wraith is waiting for you. There is a Health Station too. Take the lift, kill the lonely Trite on your right, the hidden Imp on the left dark corner, and a second Imp who teleports near the lift. There is a locked door and an open one, leading back to the exterior.

Once outside, kill the 2 Cacodemons hovering around. Follow the catwalk, which leads to a ladder. It leads to a platform, at the end of which there is a door, behind there is a jumping Imp. You can jump from the platform to the roof of the shelter to reclaim 2 Cell Packs and a Plasma Gun.

The door leads to the thermic pump control room, and one of the challenges of the game: a jumping party between moving platforms. The goal is to reach the bottom of the room without dying. Problem is, if you only run from one to another, you won't reach the one below. And if you jump, you'll take 10 Hit Points from fall damage. It is advised to be at least at 60% Health before doing this. Start with the platform on the left (the hole in the platform must be between the wall and the ladder), then proceed counter clockwise. Count about 2 seconds before each jump. Once you reach the ground, activate the monitor to elevate a ladder allowing to return. Pick the Ammo Belt, the Rockets Box and the Grenades Pack. Jump behind the tubes to collect the Large Cell Pack and the 2 Stimpacks, then crawl under the tubes to meet Katayama. Pick the Shells Clips and his Keycard, then backtrack all the way to the shelter. On the way, you'll see some bonuses behind a grid, including a BFG Cell: don't search, you can't reach them for now. As you open the thermic pump building door, you'll face a total of 5 Cacodemons, starting with a trio, then one will replace each fallen Cacodemon until you kill all of them. You can then return to the shelter, where a lonely Wraith awaits you, and now pass through the previously locked door.

It leads to the third, and the last, room of this shelter. It houses three Trites, the second to last PDA of the game and a Clip. The door leads to the exterior.

You are then again in exterior, in a third catwalk. Next to the door is a ladder you can climb to reach some dark area. Kill the Wraith here, and observe the wall: a trap will open regularly, letting you to collect the bonuses previously seen in Thermic pump section, behind the grid. Namely: an Armor, a Machine Gun, 2 Clips, a BFG Cell, a Rockets Box and a Grenades Pack. Then return to the catwalk. You'll have to kill two Imps in succession which climbs from the bottom, then a trio of Wraiths coming from behind, then pass the door through the rocks.

This leads to one of the hardest rooms of the game: a catwalk around a rocky pillar, above lava. The difficulty here is some tiles fall in the lava, so if you don't watch your steps, you'll die without understanding what's happening. It is advised to take the right path instead the left/front one. An eternal "front and behind duo" of Imps will come at you, followed by a Chaingun Commando coming from the right corridor. Then, if you walk a bit in this corridor, you'll have to face another Imp, then two additional Chaingun Commandos will either run at you from the bottom of the corridor, or stay at its bottom, waiting to fire at you behind some crates. This corridor also houses a Rocket Box, a Stimpack and a Clip. Then, open the big door.

It is a huge cave with a great chasm on the left. There are a lot of crates here. Walk a bit, kill the Imp who hides behind crates on the left and continue to wal: an eternal "behind and before duo" of horrible Chaingun Commandos will appear, behind crates. As soon as you kill them, 5 Cacodemons will teleport in the chasm. Kill them, then take all items you can until the broken main lift. Don't forget the 4 Chainguns, 3 Clips and Stimpack in this room. Then climb to the crane and play with the monitor in the cabin. You'll have to turn it to the right, then extend the freight to the end of the crane. Then climb on the catwalk, and fall on the load, then to the tubes (collecting the Stimpack if you can). Be careful, as an Imp and a Cacodemon will appear. There are also 2 Cell Packs in one of the tubes. You can see a final shelter. Enter it, kill the Imp jumping at you from the dark left corner, take the Grenades Pack and pass the door.

You are in a big corridor. Collect the ammunition here: a Rockets Box and a Cell pack in an open crate, a Large Rockets Box under the floor (you have to crawl to find it, taking some Armor Shards in the process), a Shell Box and a Clip in an opened box, and an Ammo Belt before a pile of crates. There is a monitor you can activate. As you do this, lights will turn off, and enemies will spawn all over: two Imps, a Wraith and two Chaingun Commandos. Now the doors are open, call the lift. A Hell Knight will come at you from this lift. Kill him then take the elevator.

Once down, explore the area a bit. To your right are a Clip and a Grenades pack. To the left are 2 Medkits, and an Ammo Belt behind crates. And to the front is a big rocky pillar; if you approach it, an Arch-vile will teleport behind you, summoning Imps and Wraiths. Kill them all, and take the small tunnel on the side. Beware as there is another Wraith to the left. To the right is a door. Beware as there is an alcove to the left next this door, housing an Imp.

Behind the door is a large room with some hurting (but not killing) lava. There is a "sniper" Chaingun Commando far away, and 3 Cacodemons will teleport in. Once they are all dead, the level is finished. Travel across the lava, then enter the final room.

The final room only contains bonuses: 2 Cell Packs, a Clip, an Ammo Belt, an Armor, and 2 BFG Cells. Then take the elevator to the next level.

PDAs

 * Robert Cody

Characters

 * J. Katayama

Enemies

 * Trites
 * Imps
 * Wraiths
 * Chaingun Commandos
 * Cacodemons
 * Hell Knights
 * Arch-viles

Weapons/Items

 * Pistols
 * Shotguns
 * Machine Guns
 * Grenades
 * Chainguns
 * Plasma Guns
 * Medkits
 * Armor Shards
 * Security Armor
 * Adrenaline
 * Bullets
 * Shells
 * Clips
 * Ammo Belts
 * Plasma Cells
 * Rockets
 * 6 BFG Cells
 * Caverns Access Key Card

Cabinet Codes
None

Trivia

 * There appear to be tremors and mild quakes in this level, as Robert Cody's PDA mentions. However, Mars has no tectonic plates and, as such, no quakes ever occur on Mars. So, this is most likely the effects of Hell or demons.