Krydraxikon is an ex-Toa. He was captured by The Brotherhood of Makuta, and they cut off his left hand, and replaced it with a strange hand with tentacle-like fingers. They also gave him a staff with a rotating orb-like thing on the top. Krydraxikon worked for The Brotherhood another 200 years, then got banished to The Pit by Botar, because he made a plan to kill Mata Nui. So since then, he's been mutated by the waters of The Pit. So he can breath under water, and the fingers on his left hand have been mutated to look even more like tentacles.