As resident Magneto fanboy I know that Victor is essentially 1-1 in his encounters with Magneto. Magnus may not manipulate metal the same way Vin does, but he does it exponentially better. So splitting the career series with Erik is enough justification for me to put DoomIS winning. The only way Vin would ever beat Magneto is if he died laughing from someone trying to manipulate metal against him.
Even if it's argued that Vin is magical while Mags is straight electromagnetism, Doom's magic is crazy. Strange himself has said he could be the Sorcerer Supreme if he weren't so damn evil.
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