#3365
vanilla
Anthill: a dungeon feature found exclusively in antholes that acts as a monster spawner for ants. The ants produced will all be the same type as the anthole is, and ants will not spawn out of it when there are already a certain number of ants in the area. Eventually it stops spawning ants (perhaps with a system where it rolls every time it creates a new ant and if it fails the roll it increments an internal counter; the higher the counter gets the lower the chance of spawning more ants), or the player can prematurely destroy it by digging it.
To compensate for the extra ants spawned, antholes could no longer be packed full of ants.