Each graveyard is a flat piece of land, which means their graves are always at the same terrain level.
Graveyards are all randomly generated when the world is created, that is right before the first dwarf's arrival.
Their random aspects are:
- location (to the left or to the right, farther or closer to the shelter)
- amount of gravestones (any number from three to six).
A destroyed gravestone drops one stone and won't spawn skeletons anymore. If destroyed over night, a skeleton will spawn and avenge his grave.
Every night graveyards may spawn the following types of skeletons:
- how far the graveyard is from the shelter
- the amount and height of natural obstacles between the graveyard and the shelter
- the amount of melee skeletons spawned on a given night, that would create shield stairs to overcome those obstacles.