Phobos Lab (Doom 2016)

Phobos Lab is a classic level from Doom (2016). It is a recreation of Doom's that includes enemies from the later game, but retains the original game's pickup and decoration sprites.

This level is unlocked after finding one of its rooms hidden in the Advanced Research Complex stage. Once unlocked, the full level can be played from the "Classic Maps" tab in the Campaign menu.

Essentials
In this level you start with the pistol, chainsaw, combat shotgun, chaingun and rocket launcher.

Jump over the nukage in front of you to reach a green armor then look right to see a possessed soldier and imps ahead. Follow the narrow hallway behind these enemies until you round a corner and find a pinky and another soldier guarding two stacks of shotgun shells and a health bonus; when you collect these items you will see a walkway rise from the nukage in front of you. Go back to the starting area and head up a staircase on your right, then turn right to follow the walkway you just raised to a passage where an imp and two soldiers are guarding the yellow keycard.

Head back down the stairs and turn right to find a silver door that you can go through to find another nukage pool guarded by an imp and several soldiers. Follow the walkway round the nukage until you see a yellow door on your left and open it, then ride the elevator behind the door down to two soldiers and an imp. Step off the elevator and turn left or right to find curved staircases that you should follow to the bottom to find some soldiers; two alcoves will also open on either side of the room to reveal soldiers, imps and pinkies so ensure you avoid being cornered. Jump over the nukage at the bottom of the stairs to a ledge with a switch and flip it to lower two columns with imps and soldiers on them, then backtrack to the yellow door and open it to find that a wall ahead has opened revealing a staircase leading up to many soldiers and imps along with two pinkies. Push forward to a computer room and look in the far right corner to find a button that opens to reveal a tunnel with two soldiers and several imps; at the end of the tunnel are some steps leading down to the blue keycard, which is guarded by a pinky and some other enemies.

Flip the switch behind the key then turn round to see some steps leading down to a blue door guarded by another pinky. Behind the blue door is a tall room with several more pinkies and soldiers; luring them through the blue door is advised to force them to advance from one direction. Once the room is clear, head round the horseshoe-shaped structure in this room to reach its far side where you will find an exit door; go through it and flip the switch on your right to finish the level.

Other points of interest
After lowering the two large columns behind the yellow door, you will notice that the columns rise again when you walk out of the nukage pool. Jump up to the columns as they rise to reach two ledges holding a blue megaarmor and a box of bullets.

Secrets

 * 1) Cross the nukage at the start then look right to see a staircase. Go up it and turn round to see a green wall and two barrels behind you. This wall can be opened to reveal a shotgun, a box of shotgun shells and armor/health bonuses.
 * 2) As soon as you raise the walkway leading to the yellow key, jump over the right-hand barrier and look right to see a tan wall. Open this wall to find a rocket launcher, a blue megaarmor and some armor bonuses, as well as a passage leading back to the starting area.
 * 3) After passing through the yellow door and riding the lift down, look left or right to see two misaligned walls that are actually elevators. Interact with the elevator on your right to lower it, ride it up then open the right-hand wall to find a box of shells. You can also open the wall behind the shells to find a star-shaped teleporter surrounded by health bonuses and a medikit; the teleporter will return you to the starting area. You can also reach this area by opening the green wall on the left side of the penultimate room.
 * 4) Opposite the nukage pool containing the two large columns is a small alcove. Open the back wall to reveal a second, apparently empty, alcove then open the left-hand wall to find a chainsaw. If you open the wall behind the chainsaw then you can enter an outdoor area with medikits and a supercharge (AKA mega health).
 * 5) In the computer panel, there is a secret door to the right of the button in the corner, on the other side of the protruding pillar. Go through the door to find a chaingun, a box of bullets and a backpack.
 * 6) After going through the blue door, hug the wall to the left until you have made a U-turn. Ahead of you is a chamber with a medikit and ammo. (sector 110)