System For Epithet Erased

[icefractal]

If you want significantly crunchier, Hero system could do it easily enough. IIRC, characters mostly seem to use specific Epithet uses they've practiced rather than totally freeform, and that's what the EE system uses, I think, but if you wanted to support more freeform you could make the power stunting rules easier.

I think M&M would work too, with the proviso that Power Levels vary significantly, and possibly a house-rule that offense and defense can have separate PLs, as several of the characters have better offense than defense, or vice-versa.

Both of those, being effect-based, would also handle the non-Epithet but still superhuman capabilities some characters have.