Marvel's of deadly robotic Sentinels. However, not all mutants are as easy to identify as others. While heroes like Jean Grey and Storm can as human whenever they want, and mutants like Cyclops and Angel can hide their powers in relatively simple ways, there are mutants who can't hide their X-gene.
Here are the 12 most powerful X-Men who have prominent physical mutations that make it all but impossible to hide from the humans who hate and fear them. We're excluding any hero who can easily hide their powers, so while Cyclops may not be able to control his optic blasts and Angel has large wings, they don't quite make the cut, since both have found easy ways to mask these qualities when it's to their advantage.
What's left are the X-Men characters who can't walk down the street without the risk of angry mobs and Sentinels - mutants who various comics have noted have a very different experience of being homo superior than those like Havok and Jean Grey who can easily as human.

12 Most Powerful Mutant Heroes to Ever the Avengers
While most mutant heroes are of the X-Men, a select few have been recruited by the Avengers - here are the most powerful ever to serve.
12 Beast, aka Henry McCoy
First Appearance X-Men #1 from Stan Lee & Jack Kirby
One of the five founding of the X-Men, Hank McCoy's powers are often misunderstood. His actual mutation is physical, but it only extends to physiological features that grant him enhanced agility and strength, including enlarged hands and feet. Beast's blue fur comes from him experimenting on himself, looking for ways to mask or alter his physical mutation. Indeed, Beast has altered his genetics to the extent that he is prone to random mutations, with his body morphing back and forth between degrees of animalistic appearance.
Beast feels intense self-loathing due to his blue fur and animalistic appearance, especially during the Grant Morrison/Frank Quitely New X-Men era when he took on a pronounced feline appearance. Thankfully, Hank hasn't allowed his issues to overtake his heroism, working with both the X-Men and the Avengers to safeguard those in need, as well as acting as mutantkind's genius scientist in chief.
While mutant 'powers' can be deactivated using technology, physical mutations can't, meaning that some mutants with non-human physiology have a major advantage. This includes Wolverine, whose healing factor can be suppressed using widely available tech, but who can still pop his claws in the same circumstances.
11 Nightcrawler, aka Kurt Wagner
First Appearance Giant-Size X-Men #1 from Len Wein & Dave Cockrum
The son of Mystique and Destiny, Kurt Wagner's mutant gift allows him to teleport by ing through the mysterious Brimstone Dimension. However, Nightcrawler also has a range of physical mutations, including blue fur and a long prehensile tail. Kurt also has adhesive pads on his three fingers and toes, allowing him to scale sheer walls with ease, and his fur interacts with light in unusual ways, allowing him to almost completely disappear when in shadow.
Like Beast, Nightcrawler has sometimes used an advanced piece of tech called an image inducer to as human. Despite the advanced hologram projected by the gadget, it's one the X-Men have used less and less over the years, partly because of its tendency to fail at the exact wrong moment.
Nightcrawler's appearance has shaped the course of his life multiple times. Indeed, Kurt was originally recruited to the X-Men after an angry mob attempted to kill him in his native .

X-Men: Rogue Unlocking Her Full Powers Proved She's a Mutant God
Rogue has long been one of X-Men's heaviest hitters, but unlocking her full powers proved she's more than a superhero - she's basically a god.
10 Caliban
First Appearance Uncanny X-Men #148 from Chris Claremont & Dave Cockrum
Caliban is a key member of the Morlocks - a group of mutants who live in the sewers under New York, specifically because they have mutations that prevent them from living unmolested in the human world. Caliban is perhaps the world's greatest tracker, able to sense other mutants at incredible distances. Caliban has other mutant powers which he rarely employs, including superstrength and the ability to amplify and project fear. Caliban has transformed multiple times over the years, with both a skinny form and a larger, more muscular build.
Caliban was played by Stephen Merchant in 2017's Logan movie.
9 Lockheed
First Appearance Uncanny X-Men #166 from Chris Claremont & Paul Smith
Lockheed is one of the longest-serving X-Men heroes who isn't actually a mutant. Instead, Lockheed is from an alien species known as the Flock, with biological abilities similar to a dragon. Lockheed can fly, has enhanced empathetic senses, and can breathe fire. While Lockheed pretends to have the intelligence of a household pet, he actually has sentience equal to a human and has worked with S.W.O.R.D. in the past as an undercover agent. He's also one of the founding of the Pet Avengers, working alongside animals connected to the Avengers, Fantastic Four and X-Men to combat cosmic threats.
X-Men comics often examine the politics of whether mutants can as human, with different creative teams adopting different perspectives. Notably, when Havok decried the perceived difference between mutants and humans in Uncanny Avengers, saying he didn't want to be referred to as a 'mutant,' Kitty Pryde hit back in All-New X-Men, objecting that "he sure as hell ain't talking for me."
Likewise, the fraught relationship between the Morlocks and X-Men is used to examine the difference between those mutants who are 'acceptable' to humanity and those who aren't. Recent comics have even implied that in choosing his X-Men, Professor X chose mutants who would be acceptable to human sensibilities, with Magneto more willing to recruit those with visible mutations.
8 Mercury, aka Cessily Kincaid
First Appearance New Mutants #2 from Christina Weir, Nunzio DeFilippis & Keron Grant
Mercury is essentially Terminator 2's T-1000, made of liquid metal that she can shift into endless configurations. While this includes a humanoid form, Mercury doesn't have the ability to shift back to a flesh and blood form. A member of the New X-Men, Cessily Kincaid has trained hard to control her powers, which initially reduced her to a powerless puddle. Mercury's body is almost impossible to destroy and has a high level of resistance to telepathic and mystical attack, as well as most traditional forms of detection. Currently, Mercury tends to shape her body into blades and blunt weapons, but she's still at the beginning of her mutant journey, and her powers could still grow in sophistication.

10 Strongest X-Men Heroes of All Time (Ranked by Physical Strength)
The X-Men boast some of the strongest heroes in the Marvel Universe - here are their most physically powerful of all time.
7 Face
First Appearance New Mutants #16 from Zeb Wells & Leonard Kirk
One of X-Men's most tragic mutants, Face has been heavily experimented on to make his power as destructive as possible. After being kidnapped as a baby in an attempt to bring the demonic realm of Limbo to Earth, Face was handed over to the US government's Project Purgatory. When Face's powers activated without mutant expertise or aid, his face was destroyed, removing his ability to speak, smell, hear and see. Project Purgatory then fitted a grill over his face, allowing them to trigger his power at will.
Face is able to fire highly destructive beams of force from his brain stem, powerful enough to kill multiple people with a single blast. Once rescued by the X-Men, Face was aided by various telepaths, making it easier for him to communicate and perceive the world around him.
6 Warlock
First Appearance New Mutants #18 from Chris Claremont & Bill Sienkiewicz
Warlock is a mutant member of the Technarchy, a 'techno-organic' race of robotic beings where parents and children fight to the death as a way of enforcing a warped evolutionary philosophy. Lacking the natural urge to kill his father, Warlock escaped to Earth, ing the young heroes known as the New Mutants and developing a particular bond with Douglas Ramsey's Cypher, with who he can bond on a biological level.
Warlock is able to interface with all forms of Earth technology, as well as shapeshifting his body into various mechanisms and devices. He's also able to consume biological matter by spreading his Technarchy biology. Warlock has a unique appearance and manner of speaking, though he is capable of 'hiding' in/on other lifeforms by bonding with their bodies.

30 Most Powerful Marvel Comics Characters Right Now (Ranked Weakest to Strongest)
Here are the 30 gods, mutants, sorcerers and robots that currently hold the top spot when it comes to power in the Marvel Universe.
5 Transonic, aka Laurie Tromette
First Appearance Uncanny X-Men #526 from Matt Fraction and Whilce Portacio
One of the five mutants to manifest powers following the birth of Hope Summers, Laurie Tromette's Transonic transformed into a permanent blue-skinned form. Transonic possesses the power of flight, with her mutation constantly morphing her body into the most aerodynamic form, from a formless torpedo to a large, fairy-like winged being. This power makes Transonic one of the fastest speedsters in the Marvel Universe when in flight, though she lacks the ability to return to a fully human form, seeing her powers as much as a curse as a blessing.
4 Doop
First Appearance X-Force #116 from Peter Milligan & Mike Allred
One of the weirdest beings in X-Men lore, Doop isn't actually a mutant... probably. Like Deadpool, Doop has shown the ability to break the fourth wall and even pause time, demonstrating a fluid relationship with continuity and even reality itself. Doop has demonstrated a range of abilities, including containing a pocket dimension where he can alter the rules of physics and reality (for instance, swallowing Thor's hammer then spitting out dozens of copies.) He is also seemingly hyper-attractive to humans, though it's unclear if this is a power or simply raw charisma.
Doop was introduced as the videographer for the hero team X-Statix, with implications that he might be controlling their lives as part of his desire to make pop art. Since the team disbanded, he's worked with the X-Men in Utopia, the Jean Grey School and Krakoa, generally staying close to his old friend and ally Wolverine.
3 Chamber, Jonothon Starsmore
First Appearance Generation X #1 from Scott Lobdell & Chris Bachalo
Like Face, the emergence of Jonothon Starsmore's mutant powers destroyed part of his body, incinerating several of his internal organs as well as his lower jaw and chest. Chamber is kept alive by the furnace of psionic power that is his mutant power, allowing him to unleash blasts of fire and manipulate outside power sources. After having his mutant gifts enhanced by Apocalypse, it's been speculated that Chamber is now an Omega-level mutant in of his destructive potential.

Check Out the New Codenames & Costumes the Founding X-Men Were Meant to Adopt After Graduating Xavier's School
After ditching Xavier, the founding X-Men also became solo heroes with new designs and costume - meet Redwing, Jack Frost and more.