All trap examples can be played in traps.wad

Monster Closet

Monsters are staged in a hidden room with a door disguised as a wall or other nondescript panel, which opens to surprise the player.

  • Create a hidden closet sector (A), add some monsters inside it.
  • Create a closet door sector (B).
  • Close the closet door so that it looks like a normal wall (C).
  • Apply a fresh tag to the closet door sector (B).
  • Add the trigger lines that will open the closet, and apply the same tag on them (D).
  • Assign the linedef special Type 109 W1 Open and stay fast to the trigger lines (D).

Monster Platform

Monsters are staged on top a platform that lowers from the ceiling to surprise the player.

  • Add the platform sectors with some monsters in them (A).
  • Raise the platform floors and ceilings (B) until flush with the surrouning ceiling.
  • Select the platform sectors and apply a fresh tag (A).
  • Insert vertices along a wall to make a 64 unit long line, for the switch (C).
  • Set a switch texture (C).
  • Apply the platform tags to the switch linedef (C).
  • Set the switch linedef (C) type to 23 S1 Floor down LEF.


The ceiling lowers to crush the player.

  • Assign a fresh tag to the sector that will do the crushing (A).
  • Create a linedef that will act as the walk-over trigger (B).
  • Assign the same tag to the trigger linedef (B).
  • Set the trigger linedef (B) Type 6 W1 Crusher /fast


You will need to lower unpeg the room sector walls (C) if you do not want the walls to move up and down with the crushing ceiling.


Fast crushers do less damage and the player may even survive one round of crushing. Slow crushers take their time, dealing a lot of damage and ensures player death.

Drop Trap

The floor drops out unexpectly from beneath the player into a room with monsters.

  • Add the sector that will drop out beneath the player (A).
  • Tag the sector (A).
  • Add the hidden room the player will drop into, lower it’s floor (B).
  • Insert vertices on a wall to create a switch (C).
  • Set the tag of the switch linedef (C) to match the drop sector (A).
  • Set the switch linedef Type 123 SR Lift Lower /fast (C).

Lock-In Trap

Lock all the exits in a room, forcing the player into close combat for a short time.

  • Create the open door sector (A) and assign a fresh tag to it.
  • Add the linedef that will trigger the door to close (B).
  • Set the linedef Type 16 W1 Close for 30s


If you want to close multiple doors in the room, give them all the same tag.

Teleport Ambush

Monsters stationed in a hidden room wake up to the sound of gunfire, walk over a teleport trigger and summon themselves to the designated location.

  • Apply a fresh tag to the sector where the monsters will teleport into (A).
  • Insert the Teleport exit thing (type 14, under the “Player” category called TFOG) in the sector (A).
  • Create a hidden room where the monsters are stationed (D).
  • Connect the main sector (A) with the hidden room (D) via a sound pipe (B). This allows the sound of gunfire to reach the hidden room, alerting the monsters.
  • Insert a teleport trigger linedef in the hidden room (C), assign the same tag as the exit sector (A), and set the Type 97 WR Teleport.


Use the Sound Sector Rendering mode (under the View menu), and enter sector edit mode in the 2D view to see how sound travels in your map.

Combat Teleporting

Monsters teleport around the player during combat, making engagements less predictable. This trap is used in Doom II map 10 to great effect with a Cyberdemon.

  • Create teleport trigger linedefs of Type 126 WR Teleport /mon (A).
  • Apply a fresh tag to the trigger line (A).
  • Apply the same tag to a destination sector (B)
  • Place a Teleport exit in the destination sector (B).
  • Repeat as needed, more teleport triggers with different destinations will make for varied encounters.

Nukage Surprise

A floor turns into radioactive waste, dealing damage to the player when walked on.

  • Add a trigger line of Type 37 W1 Floor down LEF /NXP (A).
  • Apply a fresh tag to the trigger line (A).
  • Tag the target sector (B) the same as the trigger tag.
  • The target sector (B) must be surrounded by damage sectors (C).
  • The damage sectors (C) are lower than the target sector (B).
  • The damage sectors (C) have Type 7 Damage 5% and the NUKAGE1 texture. On trigger the target sector (B) will lower to the damage sectors (C) and the damage and texture is transferred.