Marvel Comics secretly retconned the origin of Juggernaut, using the Black Knight's battle with the God of Symbiotes to subtly redefine the antihero's demonic patron. Decades ago, Cain Marko — the hostile stepbrother of Professor Charles Xavier — stumbled into the Temple of Cyttorak. He touched the legendary Crystal of Cyttorak, and was forevermore transformed into a human Juggernaut — a force of destruction whose role on Earth was to bring honor to Cyttorak's name.
But Cain Marko was not the first Juggernaut. Cyttorak has had countless other avatars across the ages, who were granted his power to act on his behalf on Earth. Marko's predecessor was Jin Taiko, who served Cyttorak well for decades. But when Taiko's village began to worship another god, and Taiko refused to punish them for this affront, Cyttorak chose Marko to take his place. Like every Juggernaut before him, Cain's first task was to find his predecessor and kill him in battle. He accomplished this, proving himself worthy of the mantle of the Juggernaut, and as commanded his second mission was to destroy all trace of Taiko by burning his village to the ground and slaying every man, woman and child who lived there. This dark practice means that the history of Cyttorak's past Juggernauts is sparse and — as Black Knight later proved — woefully incomplete.
Related: X-Men's New Juggernaut Is An Omega-Level Mutant Assassin
The disturbing truth is revealed in the King in Black: Black Knight one-shot by Si Spurrier and Jesus Saiz, in which the monstrous being named Knull reflects on the Elder Gods who ruled Earth in primeval times. Knull's narrative is concerned with revealing the dark truth behind Black Knight's powers — that the Ebony Blade actually draws power
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