The Door of Heaven
Many dungeons rely on elaborate traps that have to be reset or reloaded, like poison darts or the giant rolling stone that crushes everyone in it's way. Who poisons and loads all of these darts, or who were the poor slaves forced to roll the giant boulder into place? The Door of Heaven is a passive 'trap' that prevents intruders from penetrating into the heart of a dungeon too quickly, or too easily.
The Door of Heaven is created when a corridor is split into two levels. The lower level effectively dead-ends into a steeply curved ramp. The Door of Heaven is located 12 to 16 feet above the ground level. A kind DM can have the door be a figure of speech and the players need only surmount the ramp and reach the next section of the corridor. A cruel and devious DM would have a proper door 15 feet above the ground that would require some innovation to breach. Someone is asking why is there a ramp? With a curved surface leading away from the doorway/passage, the players are not going to be able to deploy conventional wall breaching tactics. They will have to have a very long ladder if they want to have any sort of secure footing. And if the players have found a way to bring a 20 foot ladder or scaffolding into a dungeon you have failed as a DM. The slope of the ramp would limit the feasibility of creating a human ladder to push a single member up and over the ledge or up to the door.
The idea means of entrance is the best running start possible with associated athletics and jumping ability checks. This should be a difficult physical challenge. Ideally, only the unencumbered thief with a solid dexterity score should be able to pull it off. Of course, the strong fighter, likely divested of weapons and armor should be able to make it as well. Non physical characters should not really be able to run and jump this obstacle. Once the first character is up, ropes can be tied, or a rope ladder can be tossed down and one at a time everyone starts coming up. Sounds like a really sweet time to make a random encounter check.
MAGIC! A wizard that knows the proper spells could levitate over the ramp, it has no magical powers. Also summoning a creature capable of crawling up vertical surfaces would also do the trick. There is also the avenue of the enchanted rope snaking its way up and tieing off to an iron loop and everyone climbing up.
BRUTE FORCE! Using hammers and iron spikes the wall can be punctured and climbed like a cliff face. It is masonry.
CHEMISTRY! A potion of spider climbing, adhesive gloves, and the like could be used. In a similar mind, boots of leaping, and similar movement aiding magic items would also be beneficial.
Additional Ideas (1)
Additional complications to increase difficulty and/or lethality without too much effort on the builder's part:
- The floor is covered in Grease (or ice).
- The floor is covered in Grease, then set on fire.
- The floor is covered in Grease, set on fire, and produces noxious fumes.
- There is a very strong wind coming from the direction of the door.
- A strong magnet makes the climb impossible in armor.
- The Door of Heaven is an illusion to buy time for the guards. The real door is hidden at the base of the ledge. (Who wants to climb that ledge every day anyways?)
- A lever at one end of the corridor opens the door, which shuts after a short amount of time.
- The walls are covered in a poisonous fungus that should not be touched.
- Any archers or foes up the slope get bonuses to attack and damage for having the high ground.