Trap CRs - Am I missing something here?

[Drakevarg]

This weekend I restarted my campaign after a TPK. As is sort of tradition for the setting, each party starts out in a "Hellcube" an 11x11 series of 10x10x10 rooms, all of which are trapped except the first room and the four exits. The rooms loop on each other infinitely, meaning you can't just keep going until you hit a wall. Furthermore, each room is entered not by a door but by a teleporter, so it's impossible to search the room for traps before entering it. Plus, the traps reset each time someone else entered the room.

Now, to circumvent the ridiculous lethality of the place (the shortest possible route involves triggering nine traps), death is non-permanent while in the Hellcube. Anyone who dies simply wakes up in the starting room again with any poison effects or burnt spells reset. I think in future Hellcubes I'll give a Wisdom penalty from death to show the victims slowly going insane from repeated disembowelment in order to give it a sense of urgency, but since I didn't think of that until halfway through yesterday's session it didn't apply this time around.

Anyway, here's the issue I had with the entire situation: supposedly, every single trap I used was level-appropriate, more or less. The PCs and by extension most of the traps were level 5. I put in a few CR 6 traps in there at key points, and a number of CR 4 traps to make up for the more deadly ones.

For traps that were supposedly level-appropriate, they were surprisingly lethal. Of the twelve different traps I placed in the dungeon, only a few of them were consistantly evaded (a dart trap was rendered harmless with an application of Protection From Arrows, and the magical traps were easily evaded by the rogue with Evasion).

Is there something I'm missing here? Some supplementary guide to inform me of how much caution I should exercise while using traps? Or was it the sheer frequency that turned this into even more of a meatgrinder than originally intended? Because something is clearly wrong when the PCs are getting annoyed when their stabilization rolls are succeeding, leaving them unconscious instead of back in the starting room.

Oh, and for reference, these are the traps I used, all from the DMG:

CR 4-
Lightning Bolt Trap x8
Pit Trap (80 ft.) x8
Water-Filled Room Trap x8

CR 5-
Poison Wall Spikes x12
Fusillade of Darts x20
Falling Block Trap x20
Fireball Trap x20

CR 6-
Fusillade of Spears x4
Flame Strike Trap x4
Compacting Room x4
Spiked Pit Trap (100 ft.) x4
Glyph of Warding (Blast) x4

[Boci]

Its not entierly clear but you said they cannot search for traps before entering the room. Does that mean they sometimes arrieve and immediatly trigger a trap?

Also, how many are triggered before they drop? Anything after 4 is meant to be pushing them.

Traps are the CR nightmare of being all or nothing. 2 successful skill checks render them defeated, so the one time they do get to damage the party they are designed to hurt.

[Drakevarg]

Its not entierly clear but you said they cannot search for traps before entering the room. Does that mean they sometimes arrieve and immediatly trigger a trap?

It means they always trigger the trap. The question is whether or not they can evade it. Unfortunately for them, many of the traps involve an attack roll, and the attack bonus is high enough that it makes it hard for even the party tank to survive. And for everyone who isn't the rogue, the ones that offer Reflex saves (excluding the pit traps) still hurt even when they are successful.


Also, how many are triggered before they drop? Anything after 4 is meant to be pushing them.

Usually they're killed after 2 or 3 unsuccessfully evaded traps. Occasionally they're killed outright after just one. This is largely because they quickly realized that they were immortal while in this dungeon and so they didn't bother healing anyone except the rogue, so she could attempt to disable the traps without needing to reenter the room, thereby springing the trap again.


Traps are the CR nightmare of being all or nothing. 2 successful skill checks render them defeated, so the one time they do get to damage the party they are designed to hurt.

True. Though in future Hellcubes I should probably make every trap have a special trick to rendering them harmless without disabling them, like the darts vs. Protection from Arrows thing.

[Boci]

True. Though in future Hellcubes I should probably make every trap have a special trick to rendering them harmless without disabling them, like the darts vs. Protection from Arrows thing.

That helps, but its finite resource (spells) bersus infinite (skill checks). Also, your party has a 50% chance of dying from 5 CR apropriate encounters. You are making them face much more.

If you ever do this again with less respawning, I would use lower CR traps to account for the difficulties of the setting.

[Drakevarg]

If you ever do this again with less respawning, I would use lower CR traps to account for the difficulties of the setting.

What would you say is a good rule of thumb? CR -2, opposite of increasing the encounter difficulty for doubled party size?

[Boci]

What would you say is a good rule of thumb? CR -2, opposite of increasing the encounter difficulty for doubled party size?

I honestly do not know. -2 CR slounds resonable. If you have the time you could try running some tests, see what comes up.

[Dimers]

The reason the CR seems lower than the lethality level is that in standard usage there are ways to avoid traps. With no chance to find or disarm the traps before they go off, the characters are always getting the nastiest effect that the trap can have. Compare it to a monster with several SLAs getting to use them all on the whole group without the PCs getting to take actions -- such a monster would also seem to have a really low CR when rated against its lethality.