House of Pain (Doom 2016)

House of Pain 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 a part of it hidden in the Necropolis 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, plasma rifle and rocket launcher.

Go up the staircase in front of you and follow the tunnel to a gray door; behind it is a fleshy area with possessed soldiers, lost souls and a pinky guarding two pits. Avoid dropping into the pits as this will activate the crushers above them; instead, walk between the pits to the three switches at the back of the room and flip all three to raise the pits (containing a chaingun and an invulnerability pickup) and open a nearby door. Turn right and head through a crossroads guarded by a pinky and some imps to a large marble-brick area, then follow the path until you reach three wide hallways that contain more imps and pinkies. At the end of the right-hand hall are some lost souls and a Hell knight guarding the blue skull key.

With the blue key, go down the middle hallway past some barrels and open the blue door at the end to find some imps guarding another door as well as a brown tech wall; the area behind the door is optional, so open the tech wall and go round the corner to see a red floor in front of two sealed doors. Step on the red floor to open an alcove on your right with a pinky, step into the water pool in the corner of the room to open the first door then enter the pinky's alcove to open the second door. Go through and follow the path until you reach some imps, then continue on to two columns that have skull switches on them which open the doors in this room. Press the left switch on the left-hand column to open one of the doors on the left-hand side leading to a pinky guarding the yellow skull key, then press the switch facing you on the right-hand column as well as the switch on its opposite face to open both doors on the right-hand side of the room. Go to the right-hand side of the room and enter the chamber furthest away from you to find some soldiers and a lost soul protecting a locked wall that you can open to find the red skull key.

With the red key, enter the other chamber on the right-hand side to find a second locked wall that needs the red key then open it to find a hallway with three alcoves. Go past the soldiers and lost soul in these alcoves to enter a red passage with several medikits, then follow it past a cacodemon and a knight to a tan room with a switch (flipping it is optional). There are two pinkies in a pit below; go down the steps on your left to enter the pit safely and walk past the pinkies to another tech wall that can be opened, follow the hallway behind it to the exit door and step on the white teleporter pad behind it to finish the level.

Other points of interest
From the start, enter the fleshy room on your right containing two soldiers and a pinky. There is a slightly recessed wall in one corner of the room; open it to find a shotgun, stimpacks and boxes of bullets and shells.

From the start, enter the room on your left to find a winding path over a blood pool. Follow the path past a pinky to a gray door with a berserk pack behind it; watch out for the pinky and lost soul that are revealed behind a wall when you take the items.

In the blue key area with three wide hallways, go down the left-hand hallway to find two doors at the end. The right-hand door hides a green armor pickup and other items, while the left-hand door only hides a box of bullets.

After passing through the blue door, take the door on the left. Continue along this path through another two doors until you reach a room with several soldiers and three other exits. Open the door furthest away from you to reveal some imps; there is a pentagram wall behind them that can be opened to reveal a knight guarding a supercharge (AKA mega health).

Near the end of the level you will reach a tan room with a switch. Flip the switch to open a door behind you and reveal a second switch, then flip that as well to reveal a blue megaarmor and a box of bullets.

Secrets

 * 1) From the start, go left and walk along the path crossing a blood pool. Resting in the blood at the far end of the room is a teleporter; go through it to reach an otherwise inaccessible area from where you can shoot from a small hole in the wall.
 * 2) After passing through the blue door, take the door on the left. Continue along this path through another two doors until you reach a room with several soldiers and three other exits. Take the exit to the left. Inside this next room is a V-shaped wall; open it to reveal a pinky guarding two medikits, two energy cells and six boxes of rockets.
 * 3) From secret #2, return to the previous room. Take the small door to the north. Walk through the lava and flip the switch on the other side to raise a pit containing a BFG-9000.

Bugs

 * If you raise the pits in the crusher room before activating the crushers, the crushers will appear to sink below the floor when they lower.
 * The invulnerability pickup adjacent to the yellow key room has the 2016 version of this item floating above it.

Trivia

 * In the blue key area with three wide hallways, go down the left-hand hallway to find two doors at the end. In the original level, if you went through the left-hand door and it closed behind you then you would have to fight a cacodemon to reach a button that would open the door again; this trap is retained in the recreation, but can be skipped as the door can be opened from both sides.
 * In the recreation, the red hallway area near the end of the level is not harmful.