[RPG] How to have a sentient dungeon (or race thereof) in the story


Lately I have seen many books (e.g.) that work on the premise of a dungeon being a sentient creature. In those books dungeons are large crystals that are capable of creating monsters as well as traps through various methods. They are killed when their crystal is destroyed.

How can I have a similar setting element in my own story? Is there a race similiar to those dungeon crystals or is there a spell that can be used to create a living creature that will control a certain building, doing repairs to it and expanding it whilst protecting it from intruders? Homebrew races are also acceptable.

Best Answer

"Construct" a Dungeon (pun intended)....

After some research spawned by A_Soo's comment/suggestion, I have discovered another option.

The Stronghold Builder's Guidebook is a 3.0 source (but as it was never updated to 3.5 it is still current material for all 3.x games) that covers in extensive detail constructing any sort of stronghold: a lonely wizards tower, a cottage, a minor keep, a huge castle, a dungeon complex... even mobile strongholds are covered: walking, swimming, flying; not to mention traps, wondrous architecture, magic items, portals, multi-dimensional aspects, and more.

Some points of note:

Stronghold Space: An abstract measure of volume within a building. While stronghold spaces don’t have a fixed size, an average stronghold space is equivalent to a 20-foot-by-20-foot room with a 10-foot-high ceiling.

Table 1–4: Stronghold Sizes

Stronghold Type Size in Stronghold Spaces
Cottage 1
Simple house 4
Grand house 7
Mansion 15
Border tower 4
Keep 12
Castle 20
Huge castle 80
Small dungeon* 30–60
Medium dungeon** 60–120
Large dungeon† 120 and up

*Such as the sample dungeon provided in Chapter 4 of the DUNGEON MASTER’s Guide.
**Such as the dungeon found in The Sunless Citadel.
†Such as the Crater Ridge Mines found in Return to the Temple of Elemental Evil.

Wondrous Architecture: Essentially a stationary magic item. Wondrous architecture often covers an entire stronghold space.

(Note that a Wondrous Architecture could also cover more than one stronghold space... you simply calculate how many spaces you want to cover and then pay the cost of the effect x the number of spaces covered.)

You can tie your stronghold’s mobility to a single object within the stronghold (which may be activated by anyone touching the object and uttering a command word), a location within the stronghold (which may be activated by anyone standing within the location and uttering a command word) or to a single creature within the stronghold (who can activate the movement from anywhere within the stronghold with a command word).

(The keyed item or room or creature mentioned here is what could become the Dungeon Core. There are a number of large crystal orbs mentioned in the SBG, normally used for weather control, but they could certainly be repurposed as a DungeonCore.)

Remember that dungeons are a form of stronghold. Even when you’re not building strongholds for characters, you can use the wondrous architecture presented here to spice up your dungeons.

So, combining all of these with DMG p.269, Table 7–30: Item Intelligence, Wisdom, Charisma, and Capabilities which indicates the cost for making an item... such as a crystal orb or stronghold space... intelligent. In order to make an entire dungeon intelligent, you'd simply need to pay the Base Price Modifier from Table 7-30 times the number of stronghold spaces your dungeon takes up.

The Leadership feat provides minions, the Landlord feat (from the SBG) provides a pool of funds to build (or expand) a dungeon, and once your dungeon is intelligent...

Intelligent items can actually be considered creatures because they have Intelligence, Wisdom, and Charisma scores. Treat them as constructs (see page 307 of the Monster Manual). Intelligent items often have the ability to illuminate their surroundings at will (as magic weapons do); many cannot see otherwise.

... the dungeon is now considered a massive construct in it's own right. Once it is a construct, it could take construct levels in order to gain more hit points and feats and skill points, not to mention potentially other class levels.

The Monster Manual gives the rule we need to allow Intelligent items to gain construct hit dice:

Increased Hit Dice: Intelligent creatures that are not humanoid in shape, and nonintelligent monsters, can advance by increasing their Hit Dice. Creatures with increased Hit Dice are usually superior specimens of their race, bigger and more powerful than their run-of-the-mill fellows.

There is even a type of ooze which can summon creatures... just in case you want to go all literal with your linked example. Maybe it could be your first cohort or minion.

So, go all crazy and build the Goblin Labyrinth from the movie, or have fun starting off with a single room.