Spinal

Spinal is a complete maniac, having been driven insane by the wild pull of the Mask of the Ancients over the hundreds (or thousands) of years since his death. He cackles with glee in the midst of battle, enjoying combat to a disturbing extent. He no longer speaks and has a very one-track mind, always pursuing his prized Mask so that he may be granted great powers and freedom. Upon finally locating the artifact and finding it drained of its powers, however, he flies into a rage and begins a global crusade to find the culprit.

He was defeated by Maya in Winford and again by Shuichi and Kenshin when they helped defend Ace.