Tenuit Tenebris

Tenuit Tenebris is the title of the archdemon imprisoned within the Tower. Imprisoned within by Petra Mortis, Tenuit is an enormous, light absorbing humanoid from inside of the Black City's Tower, held in place by numerous giant stone hands sprouting from the walls of the Tower. The waste water from the inhabited cities pour over Tenuit's head, forming the black sludge that flows out from the Tower.

Tenuit intends to escape by removing the being bonding him to the tower without slaying it, and has employed Jet Edwards to bring this about. Once free, Tenuit plans to destroy the tower. The destruction of the Tower would destabilize large sections of reality and free Tenuit, creating large sections of the world that would tear mortal creatures into particles, leaving only extraplanar immortals in the ruins..

Defeating Tenuit
While Tenuit is theoretically kill-able, he can only be slain or contained by the power found in the Linchpins.