The Dungeon is alive.
The Dungeon considers the monsters that reside in it to be its children – if they are not, in fact, its “children” via some eldritch power of creation.
The treasures the monsters guard are actually the Dungeon’s treasures.
And you are trying to kill the Dungeon’s children and steal its treasures.
So, the Dungeon hates you, and is going to try to kill you, or at least, slow you down…
Advantages the Dungeon Provides its Children:
1. They have vision that allows them to see throughout the Dungeon; not merely infravision or darkvision or what have you, but full, normal, full-color vision.
2. Doors open easily for them, unless of course they are locked or otherwise barred.
3. They do not set off traps they themselves set or traps the Dungeon has manifested. Traps set by enemy denizens, however, are just as deadly to them as to the adventurers. The Dungeon does not play favorites in the internecine feuds between its children.
4. The Dungeon also protects them from most “weird” things, such as a fountain that randomly flows with healing potion, fresh water, or poison… the denizens never get the poison, again, unless it was set by an inimical group.
Ways the Dungeon Fights the Adventurers:
1. NO innate infravision or darkvision or such works in the dungeon for adventurers, regardless of race/species/ancestry. Special vision provided by spells or magic items work just fine. There may also be parts of the Dungeon where its power does not fully extend and their innate special vision works just fine (a lost Lawful shrine, or an old Dwarven delve, a natural cavern exit, etc.)
2. Doors are always stuck, and a Strength or similar check must be made to open them… unless the Dungeon wants the adventurers to enter a specific room, then the doors open all too easily.
3. 1 in 6 chance per turn (or appropriate time period based on edition) winds randomly flow through an empty room or corridor, with a chance to blow out torches and lanterns. Fogs, mists, and other obscuring features may also randomly appear; these do not affect the sight of native denizens, only the invading adventurers.
4. Fool of a Took! Sounds made by the adventurers carry far into the Dungeon; always roll for a random encounter whenever the adventurers are making too much noise, especially when they are arguing or “discussing” what to do.
5. 1 in 6 chance per turn that a spiked door or disarmed trap left behind the adventurers might “shake off” their spike or “spontaneously” re-arm. Also remember that traps do not automatically go off when a character might activate it; there is a 2 in 6 chance of a trap setting off for each character that interacts with it (i.e., walks over a pit trap) so the first character to encounter a trap is not always the victim… and a trap might not even go off on the way into the Dungeon, only to get them on the way out! This is partly due to faulty traps, partly due to the Dungeon messing with the adventurers!
6. Illusory sounds, sights, and smells randomly emanate in corridors and rooms; perhaps the scent of a dragon wafts out of an opened door, or a shining pile of coins appears upon a hidden pit trap.
7. The Dungeon might draw denizens from one part of the Dungeon to another; there is a 2 in 6 chance that a room that was cleared behind the adventurers is occupied by new monsters when they return that way, even on the same delve. Use wandering monsters if available or split off some monsters from an as-yet unencountered group; if neither remain, roll on the local Wilderness encounter table for a totally new monster until an appropriate monster is rolled (i.e., no Lawfuls, merchants, etc.).
Note that not all these ideas need be used, and they certainly do not apply to all dungeons, only living dungeons of “mythic” sort that have gained sentience and power, whether by being home to a bound eldritch entity, animated by arcane magic, or by being too close to Hell or the Abyss.
