E3M1: Hell Keep

 
Secret 
 
1. In the room before the exit room, open the hidden door on the left to reveal a rocket launcher, shotgun shells, and a stimpack (F). 
 
 
 
 
 
 

E3M2: Slough of Despair

 
Secrets 
 
1. In the “thumb” is a small lava pit. Walk over it to lower a nearby wall, revealing a chaingun. 
 
 
 
2. Below the “pinky” and “ring fingers” is a rock shaped like an arrow if you look at the automap. Open the wall this arrow is pointing to; inside is a plasma rifle and a medikit. 
 
 
 
3. At the end of the “middle finger” is an arrow on the floor pointing to a switch; flip it to get a soul sphere. 
 
 
 
 
 
 

E3M3: Pandemonium

 
Secrets 
 
1. From the start, hang a right, then turn left into a hall with several lion-faced walls. Between the last two on the right is a dark hidden hallway leading to a secret area. 
 
2. In secret #1, cross the bridge and follow the path to the end. Flip the switch to raise the sunken floor. The next room counts as a secret also. Alternatively, run across the red nukage to the berserk pack, and enter the room behind it. 
 
3. At the end of the lion-faced hall is a circular room where the path splits off in two; follow the left one and drop into the slime pool. Hidden around the right corner is a chaingun. 
 
4. Once you’ve reached the cement-walled room in the northwest (with two balconies overlooking it, one of which is fenced in), follow the narrow hall next to the fenced-in balcony. Go up the stairs to the left; the balcony itself counts as a secret. A nearby blood/lava pool contains a soul sphere and a BFG9000, the first one in the game. 
 
5. In the outdoor area with the blue door at the northern end of the map, there is a raised platform in the center of the room resembling an altar. Walk around to the back and step on the brown floor. A wall across the way and to the right will open up. Inside is a computer area map. 
 
6. Similar to secret #5, but on the opposite side of the entrance to the area. This wall must be opened manually, however. 
 
 
 
 

E3M4: House of Pain

 
Secrets 
 

Official

 

 
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. 
 
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 three other exits. Take the one to the left (south). Inside this next room is a “<” shaped wall; open it to reveal a secret. 
 
3. From secret #2, return to the previous room. Take the small door to the north. Walk through the lava and drop into the pit. A BFG rests at the bottom. Flip the switch to get out. 
 
4. After going through the red door, you’ll be in a narrow hallway with three alcoves to the right. Open the back wall of the third alcove to get a radsuit. 
 

Non-official

 

 
1. From the start, go right and in the far left corner of the room with the blood river there will be a section with a helmet armor powerup in front of it, open that section for a shotgun and some shells. 
 
 
 
 

E3M5: Unholy Cathedral

 
Secrets 
 
1. In the starting area, take the door on the very left (the door well-lit by the torches). Open the wall on the left in the following room to get a pair of light amps. 
 
2. On the west side of the map is a wide corridor lined with a series of red brick columns. There is a door on the west wall; continue through to reach a not-so-secret area with a soul sphere and plasma rifle. 
 
3. In the northwest of the map there is a bright red room with damaging floors. On one of the walls here is a pair of blue symbols. Open the section of wall between them to get a radsuit. 
 
4. Take the teleporter in the aforementioned red room. You’ll be taken to the center of the courtyard. The southern of the four structures surrounding the center teleport will have opened, and contains a yellow skull key. 
 
5. With your newly acquired yellow key, make your way to the east end of the courtyard. There is some glowing red “writing” high on the wall. Open the wall below and slightly to the right of the symbols to get a chainsaw and another soul sphere. To exit the courtyard, take the teleporter in the northwest. 
 
6. From the room you end up in after exiting the courtyard, go through either door, then the door next to it on the other side. Walk through this teleporter, and you’ll be taken to the courtyard center again. The structure north of the central teleport will open up; inside are some goodies. 
 
7. In the north of the map is a corridor shaped like an upside-down “U”. Search the outer walls on the western side of this corridor. One of them will open, leading to a secret area overlooking the bright red room from earlier. 
 
8. At the north end of the map is a red brick room with four crushers guarding switches (the blue skull key is in this room as well). Press the switch in the southeast crusher and three alcoves will open on each side of the room. The one containing a rocket launcher (the middle one on the east side) counts as a secret. 
 
9. Go through the teleporter in the southeastern corner of the courtyard from one of the doors inside the building (i.e. not from the courtyard itself). Like secrets 4 and 6, one of the structures surrounding the central teleport will open up; its inside counts as a secret. 
 
10. Same as secret #9, but use the southwestern teleporter. Again, you must enter from inside the building rather than the courtyard. 
 
 
 
 

E3M6: Mt. Erebus

 
Secrets 
 
1. Near the building you start off at, there is a vine building to the north. Open the door and inside are some teleporters. The one on the right will take you to a ledge with a plasma rifle. 
 
2. The right torch in the marble room is also a secret door open it to access a bulk cell. 
 
3. There is another platform besides the teleporter one. The platform has a chainsaw. Straferun to get it. Note that if you get the blue key BEFORE getting the chainsaw, you are not allowed to get the chainsaw and the secret anymore because getting the blue key causes the chainsaw platform to raise too high for you to reach it. 
 
4. To access the secret map E3M9: Warrens, take the teleporter to a ledge overlooking the water. Find the skull switch surrounded by short blue walls. Back up to the ledge in front of the chainsaw, aim yourself carefully, and straferun towards it, falling in through the gap in the top. Alternatively, fire a rocket at the wall to rocket jump/boost to the walled-off area. Be careful, once you enter it you cannot do anything else other than press the secret exit switch. Also, there is another invulnerability that is strongly recommended to avoid low health from the splash damage. You must be quick, because you may completely miss your chance to be invulnerable to the splash damage! There is an easier way to exit this map to E3M9. Do NOT jump into the box, just get near it, and then face the position of the switch correctly, and press the use key repeatedly until you get to the intermission screen. Note that this will NOT credit you for the secret, and therefore NOT get 100% secrets just by doing this trick. In the Super NES port of Doom, rockets do not push you back, therefore you must straferun into the blue box. 
 
 
 
 

E3M9: Warrens (Secret level)

 
Secrets 
 

Official

 

 
1. In the same place as in E3M1: Open the wall on the left in the room before the fake exit for a rocket launcher. (However, unlike E3M1, this rocket launcher is not available on Ultra-Violence mode and above.) 
 

Non-official

 

 
1. At the start kill all Imps and Cacodemon(s) then turn left and you will see a bridge with a shotgun in the middle. When you walk on the bridge it starts to sink into the lava, so quickly run to the other side of it and kill the Imp(s) (that not appear(s) on easy skill). Once you have gone through the fake exit go back to the location where the other end of the bridge used to be (where you collected the box of shells) and jump in the lava, look right and keep walking until you see a radiation suit and a BFG 9000. 
 
 
 
 

E3M7: Limbo

 
Secrets 
 
1. In the southwestern corner of the map is a pool of blood with a switch in it. Flipping this switch opens the large octagonal structure in the area to the north. Inside the structure is a pentagram with a soul sphere on it that counts as a secret. 
 
2. Directly to the southeast of the aforementioned pentagram structure is a vaguely hexagonal green marble structure. Walk around the back of this structure and two of its walls will open, revealing a secret area. 
 
3. In the northeastern corner of the map is a maze of blood-filled tunnels. From its start, head right, right, left, then right. You’ll end up at a secret platform with a BFG. 
 
4. After flipping the switch next to the red skull key in the blood maze, return to the central area after taking one of the teleporters in the maze. Go through the southern of the two blue doors in the east. In a nearby alcove is a switch; press it to lower a wall back outside. Flip a second switch behind the newly lowered wall to raise a bridge to the “teleport tube” in the southeastern corner of this room. Go through that teleport to be taken to a secret area. 
 
 
 
 

E3M8: Dis

 
Secrets 
 

Non-official

 

 
The small circular room in the middle of the arena contains a plasma rifle and combat armor (note that the doors won’t automatically close once they have been opened). Take note that once you enter this room, any doors you have not already opened manually will open automatically, leaving you open to the boss. 
 
 
 

Here we come to an end for The Ultimate DOOM Secrets for Episode 3: Inferno hope you enjoy it. If you think we forget something to include or we should make an update to the post let us know via comment, and we will fix it asap! Thanks and have a great day!