Born mutant, his powers include sharp senses, retracting claws and great regenerative ability (called a healing factor). His regenerative power slows down his aging, so his age is indeterminate. His baptismal name is James Howlett, but he took the name of his supposed biological father, Logan. He was a Canadian government guinea pig in an experiment (the Weapon X Program) in which his skeleton and claws were coated with Adamantium (indestructible fictional metal
Juggernaut is Cain Marko, half-brother of Professor Charles Xavier, his powers are derived from a mystical jewel called "The Amulet of Cyttorak", which brought him abilities that include superhuman strength, invulnerability and the ability to not be stopped when moving in linear motion.