The legend says that somewhere, in the middle of an unknown land, is a incredible ruin, filled with traps, mazes, treasures ! But nobody lives in it anymore... The only thing that is left from the builders of the ruin is some kind of strange machine that destroys any dark soul it spots. Even if it looks dark, that guardian is friendly toward humans. Probably because he remember his ancient creators.

But then... you can bring it back to life. The Guardian... shall surveil your fortresses or dungeons.