The Lich's lair of Extinct World is a location seen in "Jerry". After the Lich fulfilled his dream of destroying all life, he retired to a small dome-shaped hut made of stones. There were several bones belonging to the corpses of his victims, where he was inert to act due to the loss of his purpose. His only (presumed) visitor was BMO, who became a "friend" of the Lich, whom the former called "Jerry". Fionna, Cake, and Simon Petrikov later visit him to break the news of BMO's death.
Appearance[]
It vaguely resembles an igloo, though it is made of stone, has several partitions, and a hole for entry. There is also a small amount of rubble scattered around it.
Gallery[]
Concept art