Charnel Pit is a Vampire Counts infrastructure building in Total War: Warhammer. This mass grave acts like a locus for Necromancers and their ilk, for it contains many fresh bodies ripe for recruitment.
Background
In a world of unremitting war, a decent burial is something granted only to the few. For the remainder, a mass grave must suffice, with enough stones on top to deter wild beasts, and enough icons to draw down the blessing of the various gods of the dead. Alas, such charnel pits attract Necromancers and other dark sorcerers like vultures to carrion.