|Real name||Cain Marko|
|First appearance||Enter: Dormammu!|
|Voiced by||Travis Willingham|
Juggernaut is a large, muscle-bound mutant and member of the Lethal Legion.
Juggernaut first appears in the episode "Enter: Dormammu!" while trying to take a fractal for Doom. After he was cornered, he broke through the Great Wall and was surprised to find that the heroes had hid inside the wall and ambushed him. Then Juggernaut and everyone else where effected by Dr. Strange's magic while he was effected by a fractal, and he started spinning around on his head. Then Dr. Doom called him and he was also affected by the magic. After a little while the magic eventually wore off.