The general appearance of Mechonis is a towering, mechanical black warrior. It has no "true" face, similar to the Mechon themselves. Instead, it has red eyes arranged in an almost church or fortress-like pattern. Its body is clunky and bulky, unlike Bionis' more sleek and graceful design. The giant sword that Mechonis wields is actually the location of the Battle of Sword Valley.
Lady Meyneth is the soul of Mechonis and Zanza's equal. She wields her own Monado in combat, and is addressed as Lady Meyneth by all Machina.