Funhouse dungeon

[the_david]

As you step out of the teleportation circle into a dark and chilly room you hear the snarl of a menacing beast. Slowly you realize that the teleportation circle didn't take you to Waterdeep, but some kind of dungeon. You're trapped inside with the monsters until you can rest to prepare another teleport spell.

I saw the Teleportation Circle spell, and it was too good an opportunity to not build a funhouse dungeon around this spell. The idea behind this dungeon is that a mad mage has left the instructions to reach his teleportation circle and mislabeled them as major cities on purpose. Alternatively, the governing body of a city thought it would be fun to spread some misinformation and build a decoy so opposing forces would end up in a dungeon instead of taking over the city. Does it really matter? You thought you were teleporting to a safe location and now you messed up.

I'm not really experienced with 5e so I don't intend to DM anytime soon. Maybe I'll come up with a funhouse dungeon like this on my own someday, but for now feel free to make it your own, add rooms, improve on the concept, etc.

[Particle_Man]

If you want this dungeon to be a trap you could make it a tesseract. There are old dragon magazine articles (#17, #38, Best of Dragon Magazine) about this for earlier editions, but really the idea is edition-neutral - it is a 4-D prison, leaving one room gets you to another room but there is no "outside" so leaving the left-most room gets you to the right-most room. You can also mess with gravity and end up walking on the ceiling and such.

[the_david]

I'd rather use the tesseract dungeon for something with a bit more plot. Mostly because it's a type of dungeon that you can only use once per group. I'd also be the kind of DM who'd place the Teleportation Circle at the bottom of an oubliette, and that doesn't really fit in a tesseract.

But it's an interesting choice.