I think a particularly important metric that should be considered here is how MC faired stat-wise against his previous opponents. To my understanding, MC has been constantly punching above his weight class, taking advantage of his shapeshifting abilities to brute force opponents with regeneration and adaptability. Like, almost every fight the MC is in, he gets heavily mutilated in ways that non-Body spawn simply wouldn't have any chance of surviving. So I think that it is possible that power-wise Cole and the Twins are above MC, yet MC has the broken ability advantage which overcomes the power difference.
Well, as far as my analysis is concerned at least, would you say that MC using his Body powers, has the advantage against Evander?
We saw what happened with Devana and I don't think that somehow MC using just his tentacles, has any advantage against a Creation Superhuman. If anything, of the two siblings, she was more capable of dealing some damage to MC at will. Blows and projectiles can be dodged or blocked with summoned flesh. Bombs just manifesting on your tails.. not so much.
Now as far as the comparison with his previous enemies:
1. Against Klaus -> MC 14 Power, Klaus 17 (MC doesn't have a trait advantage)
2. Against Danica -> MC 13 Power, Danica 24. (MC has a trait advantage)
3. Against Jake -> Ella claims that MC kept his one week advantage and she can literally read Power. A Power check during the prison segment suggests that MC can potentially have more Power than Jake. (MC doesn't have a trait advantage)
4. Against Valravn -> MC 80~, Valravn 170~ (This is up to discussion, Valravn was impervious to damage against anything other than Mantis punch, MC was efficient at regenerating normal sword slashes)
5. Against Hydra Deryl -> MC 110~, Deryl 170~ (Hydra was built to counter MC, no trait advantage)
6. Against Rebis Deryl -> MC 310~, Deryl 380~ (After all this trouble, MC won using a suicide attack. Both of them had regeneration and Deryl had both a stronger body and strong enough attacks. No trait advantage.)
If you ask me, it's not that MC's powers are overpowered compared to other traits, especially the apostolic ones. It's that his powers allow him to overcome his tactical inexperience. The more MC increases his experience and his skill, the less he is reliant on his regeneration.
Attacks that may be lethal to others, give him insight and allow him to adapt. This is big, but..
Every single other Superhuman we've met is significantly more resistant to damage. The only exception is Ella's base body, which seems to be uncharacteristically squishy, but she can just ignore damage using her Powers, so she doesn't count.
Attacks that turn MC into a pile of gore, can be resisted by others. MC's tails are supposed to be part of his main body, yet Devana could destroy them.
Deryl, who is supposed to have a weak body according to his own admission, didn't seem to lose his limbs from the same attack.
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