Jean Grey as White Phoenix of the Crown.

if we are including her jean grey when she had a cosmic entitty backing her. besides her, as of right now, mr. m or franklin richards

The Marquis of Death.

mad jim jasper an franklin richards

" @geometry:
beyonder's not a mutant"

" Vance Astro said:

"The Beyonder wasn't born a mutant though right? I thought exposure to the Terrigan Mist makes you an Inhuman?"

"The Terrigen Mists, mixed with your specific and unique mutant gene, created you." -Xavier

Pretty convoluted, so take it as you will. Even if he wasn't born a mutant, he became one (like Polaris).

"

Is it just me, or are "the most powerful mutants in Marvel" some of the STUPIDEST characters ever written, who are only important for so many issues.....
 
We also forgot Jamie Braddock.

Gamesmaster.....Hey! Someone  needs to promote him...It can as well be me!

Exodus would've been on that level, if he'd have stayed on the same level as his first appearances.

"We also forgot Jamie Braddock. "

"  Nevertheless, not a human mutant.  "

" Franklin Richards "

X-man/ Nate Grey?

" @Crom-Cruach said:

" @Mutant God said:

" Franklin Richards "

this by far. "

Mad Jim Jaspers or White Phoenix of the Crown ( also known as Jean Grey) are above him. Although we will have to see what an adult Franklin can do. Nevertheless, Franklin has those blocks in his head to prevent him from going insane and Jaspers is already insane. "