Your Worst Deathtraps

[...]

I was wondering what your insanely hard-to-beat Tomb-of-Horrors Style Deathtraps were. Here's one of mine:

In Room A, you have four pillars and and two doors, one that you just came out and one that you want to enter. When you try to leave the room, the four pillars turn into Catydid Columns. This would normally not be a big deal, but those Pillars were the only things holding up the ceiling, so now it falls on you.

[atemu1234]

One for low-level is a pit trap with spikes and skeletons.

[Phelix-Mu]

Drowned (MM3) in a room that is being flooded with water. Especially nasty after a gauntlet of poisoned traps that deal Con-damage. Doubly nasty if no one in the party can tell drowned from normal zombies. Warning: Drowned punch well-above their CR, and putting them in advantageous terrain probably raises the challenge rating of the encounter even more.

[Fosco the Swift]

Some of my Favorites:

One Iron Golem in a 60ft by 60ft by 40ft room. Double doors on the North and South walls, the south doors are the ones you walk through. Every 10ft by 10ft square in the room is a random color. When the South Door(s) are opened, the furthest wall in the hallway the characters just walked through starts moving Northwards, forcing the PC's into the room. Each tile causes a different magical effect to happen, most of them fire effects (heals the Golem) and NONE of them Electrical (Damages the Golem). Since the spells either do nothing or heal it, the Golem gets to move around freely. The PC's are not so lucky of course. As a bonus, some of the spells will forcibly move the PC's to different squares (such as gust of wind). All spell effects that are triggered happen at once on their own initiative order at the end of the round. Each square can only be triggered once per round. The Northern doors only open when the Golem is killed.
All area spell effects are centered on the 10ft square that triggered it. Cones and lines aim in a random direction (roll a 1d8, never shoots up). Rays automatically target the character that triggered the spell.
Favorite Spells: Fireball, flaming sphere (attacks one of four targets. Choose four closest creatures and number them, then roll a 1d4), Burning hands, cloudkill and Delayed Blast Fireball.

The PC's enter this room via a teleportation circle. This massive room is 50ft wide and 200ft long. All spellcasting PC's are on an elevated portion on one end of the long room that is 50ft by 50ft by 50ft, the East side. The other end of the room is the same. The East wall has many different symbols on it, that each do a different thing to the room. The lower section in the middle of the area is covered in 10ft of lava. A single Pillar 15ft by 15ft and 50ft high sits in the middle of the room. All non-spellcasting PC's are on this Pillar. The spellcasters have no access to their spells in this room. The spellcasters must then carefully select symbols by guessing, reasoning out their meanings, trial and error and by random to try and get the others to the West wall where a lever waits. Symbols can create new Pillars, give magical effects to the PC's, summon monsters, blow things up or basically anything. There should be an equal number of helpful, neutral and harmful effects. None of the symbols effect PC's on the East wall.
To use this room correctly, create "flashcards" for the Players who have spellcasting characters. The symbols will be pictures or words that hint and give clues to the effect of the card. This prevents the DM from controlling what happens with each symbol. Creativity is essential, for both the DM with his symbol effects and the Players for surviving them.

More coming soon!

[Leviting]

that dance floor is brutal without the golems, but playing it to the golem's strength is ruthless. I like it.

[Azoth]

One of mine is to have the PCs enter a room that is pitch black to even darkvision (usually hightened Deeper Darkness so daylight fizzles but you can dispell it). As they enter all their light sorces snuff out. The walls are lined with teleportation circles linked to the other spaces on the wall. Inside is usually an advanced Devil or Demon that has the rappid blitz line of spells. The monster changes, but the one required trait is the ability to see in all darkness including magical.

The monster's damage is always low, but has a high to hit. I usually have the room around 20ftX20ftX20ft. Any attempt to target the creature is facing concealment miss chances, and the cramped quarters mean AoE blasts or BFC hit everyone.

The devil gets to spring attack to his delight and ends up away from the party every time. Usually party's spread out and never realize they are at most 15ft from one another due to the teleportation circles depositing them randomly about the room.

They doors only open once the demon is slain. When the demon dies, the darkness affect ends as well.

(Yes, I have had to dodge books for using this trick)

[The Grue]

Not a deathtrap, but I once confounded my party by presenting them with a metal door secured by a simple padlock.

Took them nearly an hour to get past it.

[nedz]

Not a deathtrap, but I once confounded my party by presenting them with a metal door secured by a simple padlock.

Took them nearly an hour to get past it.

I once did this with a curtain :smallbiggrin:

[atemu1234]

Room full of spikes covered in brilliant pestilence.

[Kazyan]

Low-level deathtrap I used with Tucker-esque kobolds:

1) Have a narrow ramp of ice leading up to the next room.
2) Kobold 1 readies an action to cast Blockade when something starts climbing up.
3) PCs get hit by a literal ton of wood.
4) PCs figure out how to get block out of the way of the entrance, or just let the 3 round duration expire.
5) When block disappears, Kobolds 2-5 let their readied actions to shoot Heavy Crossbows go off.

The Barbarian did not see step 5 coming after lifting the block.

[Segev]

A simple 10'x10' pit trap, 20 feet deep, with a gelatinous cube at the bottom of it.

[Telonius]

Entrance into a mountain lair. There are three caves, identical in every way. Each cave is a 30 foot recess, with a door (disguised to look like part of the cavern wall, with an eye slit) in the back. Each door has a Kobold watching out. In two of the entrances, the Kobold has a lever. As soon as the party is all inside the cavern, the kobold flips the lever. The mechanism triggers, and the entire wall (door and all) quickly moves out to the entrance of the cave, flinging the party out past the narrow trail and onto the jagged rocks below.

[Mr Adventurer]

My most successful ever was a couple of feet of opaque, filthy water in a well that the PCs think they need to investigate. Underneath the water the well is filled with green slime.

[Mr Adventurer]

Oh, and fire-immune monsters in locations where fire causes poison gas or explosions. TPK'd with that.

Both from the World's Largest Dungeon...

[Lightlawbliss]

Made a room with no breathable air in it sealed off by lots of water in a big P trap. A hidden door is closed at the top of the other end of the P trap (flush with the ground so it looks like the passage just ends) when somebody breaks the surface on the side where most people can't breathe.

For those who think I was being too cruel, the party had a warforge who often scouted ahead. I only killed two party members, and they died before the party found out the air was not breathable.

edit: almost forgot, the gas in the room would blow up if air was added to the room; dealing fire, sonic, and force damage.

[Judge_Worm]

A hallway, every 20 ft air and water switch, including the air and water in your own body. Only affects those with arcane magic effects (like items or spell stained fingers), dc 25 fort, ref, and will save, passing all three negates and ends the effect, passing two negates damage, one for half, and 0 automatically reduces to -5 hp. How to disarm it? Pull the painfully obvious lever that releases the half-farspawn chaos dragon.

[SilverSavio]

I once modified some traps for the Tomb of Horrors since I ran it once for some friends of mine, but we could not get through everything, so then I modified some of the traps to dissuade the people that were with the original run through would not metagame. And one of the traps I replaced the arrows with Dust of Choking and Sneezing. Two people died that day.

[PaucaTerrorem]

I like 'em simple. Rocks fall. Everyone dies.

[bekeleven]

A simple 10'x10' pit trap, 20 feet deep, with a gelatinous cube at the bottom of it.

Any combination of pit trap + cube is mean, but this is the simplest. I also like the one where the cube drops down on top of them after it's triggered, and the one where it's sitting on a shelf halfway up a 30ft pit (having reach the entire length of the pit).

[RhoTheWanderer]

It wasn't supposed to be a true death trap, but it almost was. The PCs were in some old caves (a former ancient dwarven citadel of sorts) and they entered a portion of cave that I described as follows:
"You see some deep, but narrow, parallel notches on either side of the walls. The corridor has a very shallow stream of water running through it. The corridor itself has small holes and alcoves in its walls perfect for housing bugs or small rodents and rivulets of water seep out of them." The corridor went north about 10-20ft before turning west for 15ft, then north again for 15ft and east for probably 20-40ft. Then there was another set of notches at the end of the corridor. As the PCs neared the end of the corridor, they saw a 15 by 15ft room at the end with a hole in its floor down which the water was running. But at about that time, one of the players stepped on a pressure plate. The stone doors (or maybe they were rusted iron? I forget) quickly slid out from the walls, sealing the corridor (the players hadn't inspected the notches). The room very slowly began to fill with water. I had several different ways I had thought up for them to escape (including the fail-safe of, if they didn't figure anything else out, they could stay in an alcove recessed into the ceiling and wall which would form an air pocket near the door. They could just repeatedly go down to the door, attack it, and come back up for air.); however, one player walked away from the table in frustration almost immediately (and, no, his character didn't wear heavy or even medium armor). Meanwhile, as the water slowly crept upward one of the PCs came up with a plan I hadn't quite seen coming: The doors were the only worked stone in the room, so the druid could cast stone to mud on the wall near the door and they could then very easily tunnel around the stone doors. It worked, the water was flushed away down the hole in the next room (into an underground river), the other player came back to the table, the party put their armor back on, and they pressed onward. One of the players mentioned that I shouldn't have mentioned the "perfect for housing bugs or small rodents" clause as it drew more attention to the possibility of bug-enemies than the fact that there's water pouring out of the holes. I agreed. Annnd that traumatic DMing moment is why I've always felt nervous using traps ever since.


Not a deathtrap, but I once confounded my party by presenting them with a metal door secured by a simple padlock.[...]

I once did this with a curtain :smallbiggrin:
:mitd:You padlocked a curtain?!?! Wha-? B-b-but, ho-? How would that even-?:smallconfused:
And, yes, I know that just a normal non-padlocked curtain would be enough to confound a party.:smallamused:

[Yael]

Per the SRD (http://www.d20srd.org/srd/classes/rogue.htm)...
Trapfinding
Rogues (and only rogues) can use the Search skill to locate traps when the task has a Difficulty Class higher than 20.

The idea is to build a trap with a Search DC lower than 20, so the Rogue has no ability to find that trap (the DC might low because of obvious marks of a trap but you should need to search for it anyway).

How so? Pit trap with a string so you trip and fall into a pithole with a gelatinous cube inside.

[DM Nate]

This last session, I had the group encounter a small jiang shi girl (http://img1.wikia.nocookie.net/__cb20120907075501/powerlisting/images/5/5e/Miyako_yoshika_by_xephyr26-d3eu339.jpg), with an explosive rune written on the paper on her face. Of course, someone went over to see what it said. :smallbiggrin:

[Killer Angel]

Not particulary deadly, but a funny one.

The usual pit 10x10 with spikes on bottom. The first character jumped across it, only to splat on the invisible wall, falling in the pit.

[Astralia123]

I have not used deadly traps anyway.

Once when my PCs were 2nd level, I set a switch in a mage's library which can control the humidity in the room. When it raises humidity, it sprays water from the roof and grants the hostile Water Merfits fast healing. If it is switched to lower the humidity, it resembles the spell-like ability of Salt Merfit and creatures in the room suffer damage due to water loss each round (this effect does not affect the space beside the walls and the floor, so creatures standing adjacent to the walls or fall unconscious are not damaged. I put a cat over there to ensure this is clearly visible. What a kind DM I am.)

They did not notice that the cat was not damaged, but made use to this drying effect to damage the water merfits and goblins.

[nedz]

Per the SRD (http://www.d20srd.org/srd/classes/rogue.htm)...

The idea is to build a trap with a Search DC lower than 20, so the Rogue has no ability to find that trap (the DC might low because of obvious marks of a trap but you should need to search for it anyway).

How so? Pit trap with a string so you trip and fall into a pithole with a gelatinous cube inside.

My Curtain had a Search DC of 8 — just to find a way through — this still stopped half the party.

[atemu1234]

I once set up a room.

On the walls were ancient elven runes (Search DC 20, Decipher Script DC 30, Reader must know Elven), which spelled out that the room was trapped. The traps were a floor that shot arrows and a ceiling that had fire traps.

[Fosco the Swift]

Per the SRD (http://www.d20srd.org/srd/classes/rogue.htm)...

The idea is to build a trap with a Search DC lower than 20, so the Rogue has no ability to find that trap (the DC might low because of obvious marks of a trap but you should need to search for it anyway).

How so? Pit trap with a string so you trip and fall into a pithole with a gelatinous cube inside.

The trapfinding class feature is specific to above 20 DC traps because ANYONE can find a trap with a DC less than 20. If the DC is higher than 20, then no matter how well you roll you can't find the trap without the trapfinding ability.

The PC's enter a room through a door. The room has a single 10ft pathway leading from the entry doors to the wall on the other side that is blank. On the left and right is water that goes from the walkway to the side walls. There are tiny holes in the ceiling (DC 30 to see). The idea is that the PC's must enter the water which extends down 40ft. There is a lever down there that can be activated easily. However, when it is activated, water begins to pour out of he small holes in the ceiling. This has no effect except fill the room with water in one minute. Once the room is filled, the blank wall that walkway led to opens up into a hall way that is already full of water. But, when it does, the water temperature starts dropping rapidly, going from uncomfortable, to extremely cold, to damaging to frozen. The PC's must then race against the spread of freezing water to prevent drowning, dieing of cold damage or being trapped in the ice that starts building up. There are occasional air pockets in the hallway to reduce the danger of drowning. Throw in a few aquatic monsters and it's a fun party for all... the DM.

[Zanos]

Drowned (MM3) in a room that is being flooded with water. Especially nasty after a gauntlet of poisoned traps that deal Con-damage. Doubly nasty if no one in the party can tell drowned from normal zombies. Warning: Drowned punch well-above their CR, and putting them in advantageous terrain probably raises the challenge rating of the encounter even more.
The best thing about Drowned is that they have +20 to hide and move silently. A Drowned can wipe a party without them ever detecting it.

[Ferronach]

The PC's enter this room via a teleportation circle. This massive room is 50ft wide and 200ft long. All spellcasting PC's are on an elevated portion on one end of the long room that is 50ft by 50ft by 50ft, the East side. The other end of the room is the same. The East wall has many different symbols on it, that each do a different thing to the room. The lower section in the middle of the area is covered in 10ft of lava. A single Pillar 15ft by 15ft and 50ft high sits in the middle of the room. All non-spellcasting PC's are on this Pillar. The spellcasters have no access to their spells in this room. The spellcasters must then carefully select symbols by guessing, reasoning out their meanings, trial and error and by random to try and get the others to the West wall where a lever waits. Symbols can create new Pillars, give magical effects to the PC's, summon monsters, blow things up or basically anything. There should be an equal number of helpful, neutral and harmful effects. None of the symbols effect PC's on the East wall.
To use this room correctly, create "flashcards" for the Players who have spellcasting characters. The symbols will be pictures or words that hint and give clues to the effect of the card. This prevents the DM from controlling what happens with each symbol. Creativity is essential, for both the DM with his symbol effects and the Players for surviving them.


I must say that I am a big fan of this one! Mind if I appropriate it into one of my games?

I once started a game and the party almost wiped in the first session.... Instead of starting in a tavern, they started in a shiny metal room 100*100*100. No it was not filled with 1000 gelatinous cubes! I may be cruel but I am not that cruel XD am i?
Anyways. They had no idea how they got there, who the other people were or why they were there. They all had their gear (seemingly untouched). They all woke up with a DC10 unskilled check to a low humming sound and a faint vibration in the floor.
If they moved within 5 feet of a wall, the wall became the new floor (think of the gravity shifting to that wall). The humming and vibration was the result of the room shrinking by 5 feet a minute.
There were no visible doors or secret ones. Each wall (including the current roof and floor) had "Waste Disposal" written in big easy to read letters on it.

To solve the room all they had to do was jump higher than 5 feet, causing them to slowly float to the centre of the cube (the centre does not move but all six walls do to create the shrinking effect). Once no weight was detected on any of the "floors" the disposal system would reset by teleporting everything in it to a "land fill." This works because the room would compact anything until all walls were within 4 feet of eachother (depending on the compressibility of whatever is in the cube at that time) causing whatever was in it to be pulled in all directions at once by gravity, thus compacting it and causing it to no longer touch any of the walls (can happen with any size of cube provided the substance in it is no longer compressible).

The party finally figured it out with 3 minutes to spare when one of the charcters tried to throw something to another one on a different wall.
It actually turned out to be a very fun room, especially when everyone was running around on different walls looking for a door of some sort.

[Khosan]

So I was not the DM for this one. I'd asked the DM if I could take the Leadership feat, not for any combat bonuses but as crafters. Eventually, my little society came under attack by an army. I had been prepared, even going so far as to send money back to them to build defenses in just such a scenario.

First of all, I was playing a Ratfolk and all my followers were Ratfolk as well. So we had a warren dug out already. There was one main entrance which I'd heavily fortified and a huge number of other potential escape routes too small for most attackers to really attack in in case anything went wrong.

The main entrance turned out to be more than enough.

The main entrance was set into the side of a cliff. A 60 foot long, 10 foot wide bridge over a 30 foot deep spike pit. The bridge was oiled up ahead of time and could be re-oiled (or re-ignited) from trap doors in the ceiling above it (about 20 feet up). On either side of the pit, the walls above the bridge were filled with murder holes, on the opposite sides of which were dozens of Ratfolk with dozens of heavy crossbows, rotating the front position as they reloaded.

At the end of the bridge, and this was a last minute addition, stood the adventuring party with a ballista.

If they ever got further, the bridge led to an upward sloping tunnel with flammable debris at the top that we were going to send rolling down if it ever came to that. It didn't, but it was there just in case, like a lot of things.

Sum total casualties for my ratfolk: Two. Nothing managed to survive long on the bridge. Only a handful of very durable attackers managed to get to us. The rest either fell into the spike pit, were pin-cushioned by crossbows, or gibbed by the ballista. The two casualties were due to a pair of incorporeal undead getting into the crossbow murder chambers.

There were some weaknesses, casters could have utterly annihilated the 1HD Ratfolk (Cloudkill would have wreaked complete havoc), but that's why the party was there. It kept the enemy's attention and we could prioritize those sorts of targets.

[Shining Wrath]

A simple 10'x10' pit trap, 20 feet deep, with a gelatinous cube at the bottom of it.

One of my fellow players says if you drop a rock into a pit and hear "splort", run.

Also, look up. Falling gelatinous cubes are NASTY.

[Phelix-Mu]

Large cavern room which characters enter halfway twixt floor and ceiling, through the only entrance. Except for a series of 10'x10' pillars at 15' intervals that extend halfway to the ceiling (one of which has collapsed and forms a little log-like island below), and a 20'x20' platform in the middle, the rest of the room is flooded with murky water.

Except for a half-circle island along the back wall, about 80' away. There the characters see a series of three, closed stone sarcophagi, surrounded by dozens of lesser coffins propped up against the wall.

Surprise #1 is that the water is full of vampire spawn, and is just deep enough to conceal them, but shallow enough that they can climb/leap out without much difficulty.

Surprise #2 is that the water is unholy water.

Surprise #3 is that several of the vamps are running divine interdiction, which severely hampers all the turn undead resources the party brought along to handle the vamp threat.

This was the scene of one of the most epic staggered retreats that any party that I've run ever attempted, as they struggled to get the five of them, two cohorts, and two npcs out of the room, with three of them unconscious/disabled at that point. I was gunning for a very challenging fight, but it was a series of really bad luck events that turned things from a stiff fight to a likely TPK. But, to the character's credit, they marshaled their resources, came up with a plan, retrieved the fallen, and held off the enemies long enough to escape. I definitely considered it a result.

[atemu1234]

One of my fellow players says if you drop a rock into a pit and hear "splort", run.

Also, look up. Falling gelatinous cubes are NASTY.

Half-Demon Half-Dragon (Red) Sentry Gelationous Ooze with ranks in climb, jump, and balance. And max advancement.

In other words, if you see it, your DM hates you.

[Khosan]

Half-Demon Half-Dragon (Red) Sentry Gelationous Ooze with ranks in climb, jump, and balance. And max advancement.

In other words, if you see it, your DM hates you.

Hide and Move Silently too. Probably Disguise too, depending on whether or not it can disguise itself as a wall.

[atemu1234]

Hide and Move Silently too. Probably Disguise too, depending on whether or not it can disguise itself as a wall.

And Ability focus feats on its abilities, because you hate your players.

[FearlessGnome]

I have something planned for a tabletop campaign I'm running. In a room that is clearly the end of the disappointingly-and-suspiciously-empty cave, there is a fountain that pings as evil. The fountain is very deep, and at the bottom a tunnel leads off to the side and into mundane darkness. The walls are stone, but there are many out of place wooden beams along the tunnel. At the end of the tunnel there is a series of locks that, yes, you probably could pick or smash your way through in a minute or so. But the tunnel is covered in antimagic sigils, and the wooden beams are there to give the low CR intelligent undead somewhere to hide until you have swum all the way to the end of the tunnel. You are starting to run low on air.

And then the grapples start.

[Fosco the Swift]

I must say that I am a big fan of this one! Mind if I appropriate it into one of my games?

Of course not! Hope you have fun with it. And in turn do you mind if I give your trap a go? I've got a specific set of people in mind who will stare at me when they find out all they needed to do is jump :smallamused:

A new meaning of slow death, just to show up Edgar Allan Poe. One 30ft by 30ft by 30ft room. No doors. No exits of any kind. One pillar in the middle. Every minute, every person is targeted with a Magic Missile originating from the pillar. The room is permanently dimensionally locked. The PC's have full access to shield, cure spells and the like, but they won't last as long as the pillar (it's hard to sleep when you keep being hit by magic missiles: no new spells). To leave: simply ask out loud, as the character "May we please leave?" To really mess with them, wait until they use "May", not "Can". Grammar matters you know :smallbiggrin:

[Andorax]

Let's see if I can recall this properly. Inflicted this on my gaming group for a one-off 15th level campaign. Better prepared, they could have easily circumvented, but it caught them off guard.

10' square lengthy corridor ends in 10' stair down, then a vertical 10' shaft both above and below, another 10' stair up, and a door at the top of the stairs.
____| |__
___ _|
\ /
| |

Shaft below drops 100', with sharp, long spikes at the bottom. Shaft above goes up 100'.

Open the door, and the chamber beyond...is filled with water. So it pushes anyone in the stairway down into the pit, overcoming flight by sheer mass and shoving the PCs down the 100' pit and onto the spikes. Ouch.

1 round later, reverse gravity triggers and the door relatches shut. PCs and tons of water fall upwards 200', and so, too, do the spikes that are merely socketed into place, not solidly affixed to the floor. Double ouch.

Of course, there are small holes that the water can drain through in the ceiling, allowing it to pour back into the chamber beyond the door. After another round has passed, the water has drained back to its original spot, and the reverse gravity...cuts out. Spikes (and PCs) proceed to fall 200' once again.

This cascade of water notifies the local golem/summoned critter (I had a spined devil on detail for this) to take the secret tunnel out and around and start resocketing the spikes back into their proper places.

[DM Nate]

You know, there's a fine difference between "appropriately-CR'd trap that can easily kill a group of people who don't work together" and "trap that summons Orcus."

[Mr Adventurer]

Also, the standard Wail of the Banshee trap in the DMG is CR 10.

[atemu1234]

You know, there's a fine difference between "appropriately-CR'd trap that can easily kill a group of people who don't work together" and "trap that summons ORCUS!"

Totally want to make that now.

[SamsDisciple]

I wasn't even there for this session but my brother ran an adventure where the party needed to hire a paranoid gnome wizard to help with an assignment they had but when they arrived he ran down a flight of stairs into the basement. The hallway led to a split level. Downstairs was a simple square grid with many intersections, not very deadly, but it took the players a long time to figure out. There were only two simple traps that were repeated several times, a reloading dart trap that only dealt 1d4 damage, and a ghost sounds trap so they always heard the gnome running away down the next corridor :smallbiggrin: they ran around getting plinked with darts for a good hour before someone decided to go upstairs and find the gnome sitting in an easy chair sipping tea! And yes they even split up to try and corral him into a corner once they found one of the corners.

[Ferronach]

Of course not! Hope you have fun with it. And in turn do you mind if I give your trap a go? I've got a specific set of people in mind who will stare at me when they find out all they needed to do is jump :smallamused:

Thanks :)! Sure thing! Make sure that eeryone is either capable of jumping the required 5 feet or that someone else in the party can hold/throw or otherwise get them high enough up to escape the localized gravity.
Also make sure to keep track of the precise height of all players, items, and familiars. If they are getting close to dying, you can discreetly make a roll and inform the 7foot 1/2 orc that his beard and hair feel funny. A flying familiar can pose a problem in this room (so can flying PCs)... akthough you can always alter how "high" the gravity goes XD