Something that comic book fans typically enjoy is ranking the power levels of comic book characters. This is especially true with X-Men fans, since there is even a specific group of mutants who are dubbed "Omega Level," meaning that they are the most powerful mutants on the planet. The trick is that there isn't an official handbook to the Marvel omega level mutants, nor is there any real substantive guideline. As a result, it is a bit unclear as to who should even be eligible for the list! That's where we come in.
For the sake of this list, we're going to use the same criteria of the Marvel Wiki, which is that we're only going to count mutants from the main Marvel Universe (or mutants who ended up as part of the main Marvel Universe) who were specifically referred to as "Omega Level" in the comic books. This eliminates a number of mutants that you might think would be classified as "Omega Level," like Magneto and Storm (or even obscure characters like Hyperstorm), who just were never officially labeled as such in the comic books. Adding to the confusion is when certain characters are dubbed "Omega level" in just a certain category, like Psylocke, who is considered an Omega-level telepath, but that is somehow different than being an overall Omega level mutant. This leaves us with 16 mutants who were officially dubbed "Omega Level." We will rank them from least powerful to most powerful.
We probably shouldn't even count Maddie on this list, as she debuted in the miniseries Deadpool vs. Old Man Logan, which has only released two issues so far, so we know very little about her. What we do know about her is that she is an Omega-Level Mutant. In the first issue of the series, Logan is tracking Maggie so he could enroll the powerful mutant in the Jean Grey School for mutants.
However, a group of operatives from Gen-Form Enterprises, a mysterious corporation that had held Maddie hostage until she escaped, show up to re-capture her. Logan and Deadpool must team-up to protect her. So far, from what we have seen, she is a powerful teleporter who can summon objects seemingly at will to attack her opponents. It seems pretty powerful, but until we see the upper limits of her abilities, we're going to keep her last on the list.
Perhaps the most hapless character on this list is Josh Foley, who oddly enough began his comic book career as part of an anti-mutant hate group. That was until, of course, he turned out to be a mutant himself. The X-Men, as it turned out, are bizarrely accepting, as his racist past was quickly forgotten as he became a well-regarded member of the next generation of mutant heroes.
Josh, code-named Elixir, had the ability to heal, but it was soon revealed that his power to heal cells could also be used to destroy cells! Thus, he could kill just as easily as heal. In addition, due to his complete control over cells (including his own), Elixir was, in effect, immortal. If he died, he would just heal his cells. That said, he also kept dying all the time, so he's not all that imposing.
Until the recent revelation that Iceman has been closeted all of these years, the most interesting plotline involving Iceman has been his lack of ability to fully embrace just how powerful he was. After his body was taken over by Emma Frost in an early 1990s plotline, Emma began to do things with Iceman's powers that he never knew how to do before.
This then began a 20-year storyline involving Iceman finally realizing his "Omega Level" destiny with his powers, only to then need to be reminded a few years later whenever a new writer would take over the series. Iceman never seemed to get just how powerful he was, despite everyone repeatedly telling him that he was super powerful (hence "Omega Level" being thrown around a lot).
For years, Mister Sinister was obsessed with Scott Summers and Jean Grey and their DNA and when we saw the child of Scott and Madelyne Pryor (who turned out to be a clone of Jean Grey), we saw why Sinister was so intrigued. Scott and Maddie's kid, Christopher Nathan Summers, had the makings of an extremely powerful mutant, with nearly limitless telekinetic abilities.
However, the baby was infected by a Techo-Organic Virus and Cyclops had to send his kid into the future to save his life. While there, the child learned how to use his powers to keep the virus at bay. He grew into the hero known as Cable and returned to the era of his birth as an older man. Since Cable has always had to keep the virus at bay (it makes him look like a cyborg), he has never been able to show his true power.
When the religious group known as the Askani asked Cyclops to bring his son into the future to cure him of the Techno-Organic Virus, they turned out to be a bit less confident than you might expect. When they got to the future, they made a clone of young baby Nathan, just on the off chance that they were unable to cure him of the virus (or were unable to keep the virus from spreading).
The non-infected clone was then kidnapped by Apocalypse to be used as a new host when Apocalypse's then-current body was burned out. Growing up under Apocalypse's tutelage, this young boy grew up to become the evil Stryfe, who looked just like his "twin," Cable. Since he did not have to keep the techno-organic virus in check, Stryfe was more powerful than Cable.
In the altered reality known as "Age of Apocalypse," there was no Cable, since Cyclops and Madelyne Pryor never got together (in fact, Maddie Pryor was not even someone who needed to exist in this reality). Instead, Mister Sinister just made a clone using Cyclops and Jean Grey's DNA and came up with a test tube baby who became known as Nate Grey.
When the "Age of Apocalypse" timeline ceased being a divergent reality, a quartet of characters made their way to the regular Marvel Universe. Nate was one of them. His powers continued to grow as he got older in the regular Marvel Universe. More recently, though, after dying (and coming back from the dead), his powers have been dramatically reduced in scope, knocking him down on this list.
One of the most surprising characters on this list is Emma Frost, who never quite seemed like she was more than a typically strong telepath. However, as the years went by (especially when she reformed, eventually becoming an outright member of the X-Men), her powers increased in relation to her fellow mutants and soon became referred to as a Omega Level mutant.
In addition, she was able to use her powers to defeat both Nate Grey and Charles Xavier (who is a notable absence from this list), which is very impressive. Most recently, she was able to use her powers to make the world (including many other telepaths) believe that Cyclops was alive and pushing the X-Men into conflict against the Inhumans, despite Cyclops dying as soon as he came into contact with the Terrigen Cloud that had spread over Earth.
When the mutant population exploded, so, too, did the student population at Xavier's school explode. Quentin Quire was one of the new students at the school and he became a prized pupil of Charles Xavier. However, Quire also was part of a new generation of mutants who were not so willing to follow the rules of human society. He helped create a riot at Xavier's as they tried to take over the school. He ended up dying in that battle due to an overdose of a power-enhancing drug that he was using.
He then recreated himself due to his incredible powers and has since become a student of the X-Men again. He remains one of the most powerful beings in the universe and recently served as a host of the Phoenix Force due to his great powers.
Christopher Summers was flying in his plane with his wife and their two sons when their ship was attacked by aliens. Christopher sent his two sons out of their ship (sharing a single parachute) but Christopher and his wife were taken prisoner by the Shi'ar. Christopher became a slave while his wife was taken as a consort of the evil Emperor D'ken of the Shi'ar. She was raped and died, but not before getting pregnant by D'ken.
Her son, Gabriel, was artificially aged and sent to Earth to work as a slave. He escaped and joined up with an early version of the X-Men. He seemingly died, but then the mutant energy released when Scarlet Witch got rid of nearly all mutants on Earth revived him, as he could absorb energy. Absorbing half the mutant energy in the world made Gabriel one of the world's most powerful mutants.
Absolon Mercator was content to just live a quiet, lonely life in the burgeoning area of New York City known as "Mutant Town." However, when Scarlet Witch de-powered most of the world's mutants, Mercator was forced to come out of his seclusion and begin to interact with the few mutants left on Earth. He went to the X-Mansion with the rest of the "198" (there were 198 registered mutants). He began to be referred to by his fellow mutants as simply "Mister M."
He showed off his stunning powers, which seemed to include nearly limitless psionic abilities. He was seemingly killed via the use of the power inhibiting mutant known as Leech, but his body disappeared from his coffin. He appeared to have evolved beyond the need for a human body!
Seven hundred years ago, the X-Gene first manifested itself in humanity with what would later be referred to as "proto-mutants." These proto-mutants were nearly entirely wiped out by the rest of the human populace, under the auspices of witch hunts. However, one of these proto-mutants, Gabriel Shepherd, managed to survive (it helped that he looked more "human").
He then lived in seclusion for the next seven hundred years, until the proto-mutants were resurrected and turned into weapons. He showed up and helped the X-Men stop the proto-mutants and he made sure that his fellow proto-mutants would never be used as weapons again. He seemed able to control his cells completely, like he could turn himself into pure energy if he so chose. He also had other notable super-powers like super-strength and strong telepathic powers.
Hope Summers is one of the odder Omega Level mutants on this list because her powers, for the most part, exist only in relation to other mutants. This is because her main ability is that of power mimicry. She can copy the power of any other mutant. Of course, since there are a whole lot of powerful mutants out there, it therefore, makes her extremely powerful.
In addition, she, too, was a host for the Phoenix Force. When the Phoenix Force came to Earth during Avengers vs. X-Men, it was trying to merge with Hope. It eventually did and Hope used her abilities (with help from the Scarlet Witch) to instead transform the Earth to bring the mutant population back to Earth for the first time since Scarlet Witch decimated the mutant population.
For years, Jean Grey just seemed like a standard telekinetic mutant. That, though, was revealed to be a result of Professor X placing a mental block on Jean when she was a young girl, as she was so powerful that he needed to keep her from going insane from her abilities. Over the years, her telepathy came forward, as well. She then seemed to develop her powers into a new being known as Phoenix. Later, that turned out to be a separate cosmic being known as the Phoenix Force.
However, as time went by, we learned that one of Jean's mutant powers was the very ability to draw the Phoenix Force to her. In other words, it was not a coincidence that the Phoenix Force came to her to begin with, as she is basically "one" with the Phoenix Force, which makes her immensely powerful.
David Haller was the son of Gabrielle Haller and Charles Xavier (unknown to Xavier). He had a normal enough childhood until he was present for a terrorist attack. The attack kickstarted his powers and led to the mental trauma that caused his name "Legion."
You see, David gained multiple personalities, but each of the personalities had its own, distinct mutant ability (most of these abilities, on their own, would be considered "Omega Level" in their categories). David had the ability to, in effect, create new mutant powers out of nowhere and each of those powers came with a personality. There seemed to be no limit to the amount of powers he could create. His abilities were so strong that he literally traveled through time at one point! He was even able, at one point, to erase himself from existence.
The son of Reed and Sue Richards (Mister Fantastic and Invisible Woman), Franklin Richards seemed like a normal child, but it soon became evident that he possessed great powers, powers that his young mind could not handle. So Reed did what any father would do, he came up with a machine that would, in effect, lobotomize his own son. Shockingly, Sue did not like this idea and they actually split up for a while.
While his actions were drastic, Reed's concern was logical, as Franklin's energy-wielding powers are almost limitless. The Celestials are actually kinda scared of Franklin. He literally created a pocket universe at the end of the Onslaught epic, so that his family could survive their defeat of Onslaught! He just did this almost casually, with little effort.
It is tough to place Matthew Malloy number one, because he only had a handful of appearances, but they certainly spent every one of those appearances telling us how powerful he was, so we guess it is only fair to have him in the top spot. Matthew did not realize he was a mutant until his wife was killed by a Skrull during the Skrull invasion of Earth. When he was lamenting her death, his powers kicked in and wiped out a whole mass of people.
The X-Men tried to deal with him and he easily killed most of them, as well. He had the ability to alter reality at his whim. He was, essentially, a god. Ultimately, one of the X-Men, Tempus, went back in time and made sure his parents never met, so that he was erased from history and all the damage he did vanished.