Cain Marko, also known as the Juggernaut, is the step-brother of X-Men founder Charles Xavier and the avatar of Cyttorak. Powered by the Crimson Gem of Cyttorak, Marko is bestowed virtually limitless brute strength and durability which he mostly uses for criminal pursuits and wanton destruction. The Juggernaut is considered one of the strongest and most powerful beings on Earth.