Marvel's Top 10 Most Powerful Mutants
My list looks a little different than most. Power isn't just about offensive abilities, and is more about self-preservation. Imagine a situation where the only beings left in the universe are mutants from Earth. Let's also add the condition that they can only do battle through use of their mutant powers. Who would survive? I contend that the answer will provide you with the list of the most powerful mutants - survival is power once everyone is on death's doorstep. These are my picks.
Magneto has been in a number of situations where he has had to fend off a massive onslaught single-handed. He not only has the power to murder through extracting iron from human blood, but he can also shift the polarity of the planet's poles. If Magneto found a stronghold (like Asteroid M) he would be able to wipe out most mutants without laying a direct finger on them. Most mutants are still human in the most fragile sense and they depend on their body's organs to survive. Magneto could exploit that both internally and externally. There are some mutants that could get to Magneto but the most basic use of his magnetism powers would be sufficient to keep them at bay physically. Magneto has a trained mind and technology geared for repelling psionic probes and attacks. Magneto is a survivor as well as a mass murderer, and that is what makes him one of the most powerful mutants alive. He has no compunction and will do anything to survive.
9. Mr Sinister
He doesn't usually make it to the top lists of most powerful mutants because recent writers have tried to get fancy with his character and remake him as an enhanced human merely imbued with X-genes for his DNA. I don't really care about anything that came after 1994 because I find it to be beating a dead horse, while it is both arbitrary and gratuitous (in other words, he didn't need demotion). The original Mr Sinister was a mutant and either had the ability to resurrect the dead or it was more that he had clones on hand. This would imply that either Sinister can resurrect or that the Sinister which is out and about is probably a telepathic proxy for the real Sinister who is always safe and sound. You can't even get to this guy so how would you kill him? Sinister is the ultimate survivalist and has the knowledge and intellect to strategize his survival plans centuries in advance. He can teleport away from threats and it seems as if his only true weakness is his ego. I believe that under duress Sinister wouldn't fool around and if he was intent on getting a perfect score in an all-out mutant war then he would find a way to achieve that goal.
Are you going to argue that the oldest mutant doesn't have a knack for survival? In over ten thousand of years, you'd think that Selene has learned a thing or two. She also has the mutant power to control inorganic material, to attack telepathically, and to drain the life force from others. When push comes to shove, Selene massacres all around her and doesn't think twice about it. Once again, the "villains" survive because the villains aren't distracted by moral and ethics. Selene is the epitome of an immoral survivor.
7. Jean Grey
Well, no one is absolutely sure that the cosmic Phoenix entity has truly left Jean Grey. At any point, she could be revisited - I mean, the nature of the Phoenix is to resurrect. As it stands, Jean is an incredibly powerful telekinetic and telepathic mind. Likely, she could render a deadly physical threat to a mass of retarded mental mush. Jean has been through a lot of psychological turmoil and has faced it with dignity. Perhaps, a Legion or Proteus would have more raw power, but if push came to shove Jean could weather their storm through her mental resolve. She could then unleash her counter-attack which petulant minds would have no defense against. Her only weakness without the Phoenix entity is that she has a heart and is ethical - this could undermine her ability to survive.
Apocalypse's whole shtick is about survival and he isn't much at risk of being destroyed when his mutant power is the ability to control his own molecules. Apocalypse cannot be destroyed by other mutants and he is able to discorporate to a degree where he would be immune from psionic based attacks. Apocalypse is ruthless and resourceful enough to destroy anyone. He might be the most powerful mutant, but simply hasn't revealed a greater range of powers. He claims to engineer technology that provides for a lot of his power, but this may be a ruse to conceal the true upper limits of his powers. It is possible that Apocalypse could defeat cosmic beings, let alone all over mutants.
This is where the list gets tricky. I have decided to rate mutant "power" based on putting all mutants up against each other but limiting them to attacks and defenses which solely utilize their mutant abilities. This means that Colossus can't revert to human form and then beat an opponent to death using regular muscle. If Colossus's mutant power was nullified then he would be useless in the war of attrition and would inevitably be defeated by a mutant that retained their powers. This is exactly what makes Wipeout powerful. He has (or had, rather) the ability to remove mutant powers. It is unclear what kind of proximity he required for this power, but there didn't seem to be any way to restore the powers unless he willed it. Wipeout might not be the sole survivor of a war of attrition among mutants but he would last a long time through negating powers and likely being protected by a powerful mutant who was interested in a temporary alliance.
4. Michael Nowlan
Nowlan was a real mess - a junkie. He abused himself to avoid the responsibilities of controlling his powers. His powers were incredible and he could augment the mutant powers of others. The augmentation could be incremental or he could push other mutants to losing total control over their powers. In a war of attrition, Nowlan would have been able to make all the mutants go haywire and quickly they would have destroyed everyone else or themselves. His powers weren't that useful to himself but they would have been considered the most powerful to an ally who was vying for supremacy. Imagine if Nowlan had increased Magneto's powers for example - then Magneto would be able to instantly kill almost everyone through iron extraction in the blood. Only a few mutants would survive an attack like that. If Nowlan was being attacked psionically, he would be able to augment the telepathic powers of his opponent to the point where they would lose control and probably fry their own brains. Nowlan's real limit was that he was his own worst enemy and a total suicide case.
If the war of attrition was based on the use mutant powers then Leech would make it until the very end because he is in a protective bubble against mutant powers through his own power to nullify the powers of others. Leech can cause all kinds of problems for mutants when they are battling. Over time, Leech trained and was able to retract his "aura" so that mutants could retain their powers even if he was in the same room as them. It remains to be seen whether he could do the opposite and train to extend the field of his powers so that it might have a global spread.
It seems like most of the top of my list is obscure mutants that few have heard of, but that should convince some that they are the most powerful - they were so overpowered that there was no feasible way to incorporate them into the Marvel universe logically. Chance has the combined mutant powers of Nowlan and Leech - she can enhance or nullify the mutant powers of others. If she had powerful allies protecting her then there would be virtually no way to destroy her. It would all depend on who she allied with.
1. Professor Xavier
All that Charles Xavier would require is a slight head start and then he could turn everyone's mind to mush prior to them articulating the first thought for their own plans. If Professor X poured it on and wasn't limited by his strong ethical core then few, if any, mutants would survive his onslaught. Professor X has been known to rewrite the memories of almost anyone with extreme ease. It seems that his greatest weakness is how his emotional sense adversely affects his logical mind. A sociopathic Prof. X would undoubtedly be the most powerful mutant.