Meta Knight is weird. A lot of his attacks actually do enough damage to be reasonable to compare to DK - at base, his sword can knock over an entire bus of Waddle Dees in Planet Robobot, something that can only be matched by the actual Robobot Armor. There's a pretty direct comparison to be made for MK having that level of strength at minimum, which would put him at least on par, if not better, than pre-transformation DK. This is to say nothing of speed and skill, which are leagues above what DK can do - keeping up with Wheelie Rider while escaping the Halberd BACKWARDS and that flight speed being consistent across boss appearances is way beyond anything DK could do.
I could see a feasible route to Meta Knight winning if he killed Pauline first. I do think base Bananza DK has no better options for Meta Knight than "throw rocks at him", and Meta Knight is actively able to heal himself and improve his speed as a fight goes on. However, a bunch of MK's best feats of "he beat Galacta Knight, the strongest warrior in the universe!" just... didn't happen, merely existing as what-ifs where he COULD do it I guess if he wanted to. Additionally, I just don't see him ganking Pauline; if DK brought a child into the fight, I feel like Meta Knight would be honorable and not kill a child. At which point, yeah dude, Kong Bananza REALLY hurts, like "I hit a man so hard it parted the clouds with his carcass" is gonna deal damage.
If Meta Knight plays the lamest game imaginable I think he takes it. Which means that the average Brawl player would win this. But nah, Donkey Kong.
Mario Vs Cloud 2002: A Video Retrospective - https://youtu.be/1dx4t6H_K9Y
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