A bone house is a variant form of instant fortress. These grim statuettes appear as skull-topped fortresses the size of a clenched fist. When activated by speaking a command word, a bone house grows to form a tower 20 feet square and 30 feet high, with arrow slits on all sides and a crenellated battlement on top. The bone walls extend 10 feet into the ground, rooting it to the spot and preventing it from being tipped over. The fortress has a small door that opens only at the command of the owner of the fortress—even knock spells can’t open the door.
The bone walls are magically enhanced to be as hard as stone, and have 100 hit points and hardness 10. A bone house can be repaired by casting inflict spells on the walls, with every 10 points of negative energy repairing 1 point of damage. A bone house springs up in just 1 round, with the door facing the device’s owner. The door opens and closes instantly at his command. People and creatures nearby (except the owner) must be careful not to be caught by the fortress’s sudden growth. Anyone caught in the area takes 10d6 points of damage (DC 19 Reflex save for half damage). The interior of a bone house is under the constant effects of a desecrate spell and is considered an altar to an evil god for the purposes of determining the desecrate modifiers.
Once a bone house is expanded into tower size, its owner can create up to four mummies per month from the drifts of bone ash and detritus that litter the inner rooms. Creating a mummy in this manner takes 10 minutes, and the owner must be inside of the bone house the entire time. Due to the desecrate effect, mummies created inside gain +2 hit points per Hit Die. These undead guard the contents of the bone house without needing to be commanded. If the owner wishes to command these mummies to perform other tasks, he must use other means to do so. No more than four mummies may be active at one time.
A bone house is deactivated by speaking a command word (different from the one used to activate it). It cannot be deactivated unless it is empty.
A bone house has hit points and hardness and can be destroyed largely by mundane means. However, to fully destroy a bone house, its final hit point must be taken by a positive energy effect, requiring a cure spell or similar effect to be cast on the nearly ruined structure.
Pathfinder Campaign Setting: Artifacts & Legends © 2012, Paizo Publishing, LLC; Author: F. Wesley Schneider.