When you examine the differences between DC Comics and Marvel Comics, one of the oddest differences comes in how they handle telepathy. Telepathy is certainly something that exists in the DC Universe, but in the Marvel Universe, it is such a common superpower that we could have easily made up a list of just Marvel telepaths that would still leave off many notable characters. Not only that, but also telepaths in the DC Universe seem to not be treated quite as powerfully as Marvel telepaths, where the power of the mind can sometimes destroy whole solar systems.
Here, we will rank the most powerful telepaths in comics. Do note that we're only ranking people whose telepathy is actually their power, and not just a side effect of their abilities. What we mean by this is that pretty much every cosmic being, like, the Living Tribunal, has telepathy, but it's just an effect of being a cosmic entity - we're not counting that as being a telepath in the typical sense, so they're not on this list. Plus, no hero whose power is to mimic another's abilities (like Rogue or Hope Summers).
Elizabeth Braddock is an interesting example of someone whose power levels went all over the place in her comic book career. When she originally debuted, she could see the future, but that was about it. When she was brought back into the "Captain Britain" feature, she was now a telepath, but not a particularly powerful one. She ended up in the United States and joined the X-Men when they were without a telepath for the first time in a while, so he she became an important member of the team.
Later on, after entering the Siege Perilous, she gained a new Asian body and abilities as a ninja. She also debuted her psychic knife, which was the focused totality of her psychic powers and could temporarily fry people's brains. She then sacrificed her telepathy in order to trap the Shadow King when he tried to conquer the world through the world's telepaths. She gained her powers back eventually.
14 CAPTAIN COMET
Something that people often mistake is that eras are almost never closely defined. To wit, there was no real cultural difference between the events of 1969 and the events of 1971, and yet one is defined as "The '60s" while the other is "The '70s." That is the situation that Captain Comet finds himself in, as he was a telepathic mutant superhero who debuted...in 1951! The early 1950s fall into a sort of "no man's land" when it comes to superheroes, as there were almost no superheros introduced in those years, so fitting Captain Comet into a particular "era" (like the Golden Age or the Silver Age) is next to impossible. He's just an outlier.
After being in comic book limbo for decades, he showed up again in the 1970s as the main hero who fought against the Secret Society of Super Villains. He then went right back into limbo, but was brought back in the excellent series, "L.E.G.I.O.N." and has hung around the periphery of the DC Universe ever since. His powers come from being the peak of human evolution (hence him being one of the first "mutant" heroes).
13 STEPFORD CUCKOOS
The Stepford Cuckoos are clones of Emma Frost, created by the evil John Sublime as part of the Weapon Plus program (they were Weapon XIV). They were originally just five of hundreds (maybe even thousands) of similar clones who were designed to be used as a devastating weapon. The clones (all inherently twins) had a special telepathic block installed in them that caused people to never question exactly where it was that they came from. Originally, there were five of them, and they called themselves the Five-in-One.
Then one of their number, Sophie, was killed during the riots at Xavier's that they helped force Quentin Quire into instigating. Later, another member of the group, Esme, turned out to secretly be working with Magneto (who was undercover as Xorn). She, also, was killed. That leaves the current trio, the "Three-in-One," namely Phoebe, Mindee and Celeste. They have a complicated relationship with Emma Frost. She is their mentor, but they have clashed with her a number of times in the past.
12 SATURN GIRL
Saturn Girl, Imra Ardeen, came from Titan, which was a colonized moon of Saturn. Everyone on Titan communicates through telepathy, but Imra was the most powerful telepath on the planet. She eventually became a founding member of the Legion of Super-Heroes (along with Cosmic Boy and Lightning Lad).
As noted earlier, DC Comics tended to not have a lot of telepathic characters, and with Saturn Girl, you could almost understand why, as it seemed like every other issue she was getting into trouble with her telepathic powers. You see, in the Silver Age, superheroes didn't trust each other very much, so they were constantly thinking that their friends were plotting against them, and this was heightened by Saturn Girl "overheating" things that she then jumped to the wrong conclusion about. It happened all the time in the early days of the Legion. She means well, though, and has always been one of the most powerful and most honorable members of the Legion.
11 EMMA FROST
With the amount of mutants in the world and the size of Charles Xavier's student body, it was no wonder that eventually someone realized, "Hey, wouldn't it make sense that there would be a rival school for mutants out there?" That's the role that Emma Froat took one when she was introduced in the middle of the "Dark Phoenix Saga," as she was vying with Professor X and the X-Men for Kitty Pryde. Emma Frost was also the White Queen of the Hellfire Club and she became a master in using her powers to switch her body with other people, something she's done a number of times over the years.
When Jean Grey died, Emma Frost became the X-Men's main telepathic presence, and over the years, she has taken on more and more of a power role in the X-Men. This was particularly highlighted recently during "Inhumans vs. X-Men" when she used her powers into making people believe that Cyclops was still alive and that he had "died" in battle with Black Bolt. She then took control of Magneto and forced him to kill a bunch of Inhumans. She is now on the run, but is about to form her own team of X-Men.
When Cable first showed up in "New Mutants," he just seemed like your standard "badass cyborg with a big gun" guy, but over time, it became clear that instead of being a cyborg, Cable was actually suffering from a disease called the Techno-Organic Virus. The virus basically transforms human body parts into machines. Once it reaches your brain, you're pretty much screwed. However, Cable was a powerful telepath and telekinetic and he would use his powers to continually keep the virus under control, so it only has taken over part of his body, making him look like a cyborg.
However, if it were not for his constant need to keep the virus under control, Cable would be one of the most powerful telepaths on the planet, something that he sometimes showed when he was willing to cut loose without worrying about the virus (like when he attacked Onslaught during the "Onslaught" crossover without regard for how it would hurt himself).
9 RACHEL GREY
In the epic storyline, "Day of Future Past," Katherine Pryde was sent into her own body in the past from 2013 to 1980 so that she could help avert an assassination that would lead to a dystopic future where Sentinels have hunted down and killed most mutants in the world. However, after succeeding, nothing changed. This led to her friend, Rachel Summers, using her powers to travel to the past where she discovered that she had actually sent Pryde into an alternate past.
Now stuck there herself, Rachel ended up bonding with the Phoenix force and becoming Phoenix for a few years before she separated from the power. Rachel is an interesting case for ranking abilities, since she technically has as much telepathic power as anyone, but she doesn't know how to use it well and has been defeated by many other telepaths, including Emma Frost, who is noticeably less powerful than her in theory (potential not being expressed is why Franklin Richards is not on the list, as he has more potential than anything).
Remember what we said about how Cable's great power is held back by the fact that he has to constantly deal with the techno-organic virus that was coursing through his body at all times? Well, as a clone of Cable, the villain known as Stryfe has never had to deal with that problem, as he was cloned without the techno-organic virus by Apocalypse in the future. Apocalypse ultimately planned on using Stryfe's body as a vessel for his own, withering old body, but instead Stryfe escaped to the present.
Stryfe is powerful enough that he actually used his powers to "turn off" Jean Grey and Cyclops' powers at one point (it was back before Jean Grey had a power boost). However, at times it seems like he is holding back a bit. Perhaps he has never met his potential since he is a clone of a child of Cyclops and another clone, Madelyne Pryor. Whatever the reason, Stryfe never seemed to be quite as powerful as you would think he should normally be, considering his genetic makeup.
7 KID OMEGA
When we first met Quinton Quire, the mutant known as Kid Omega, he was a drug-addicted fool being tricked into starting a riot at Xavier's to help impress a girl (not knowing that the power-boosting drug that he was using, Kick, was actually powered by John Sublime). Quire's mind works unlike nearly anyone else's, as he goes through thousands of thoughts every second (and the power boost from Kick didn't seem to have that much of an effect on him, so this is his natural talent level).
However, much like some of the other people below him on the list, a good deal of Quire's power is still in the potential stage. We have seen him pull off some amazing feats and the fact that he is seen as a viable host for the Phoenix Force is also very impressive, but when it comes down to actual mental battles, he has routinely been defeated. He's young enough that this likely will change, but for now, he's a bit lower on the list.
If Cable is very powerful but is being held back by the techno-organic virus and Stryfe is held back by some unknown reason (perhaps by virtue of being a clone of the son of a clone?), then Nate Grey manages to avoid both of those problems, as he is a clone made directly from the genetic material of Cyclops and Jean Grey in the "Age of Apocaylpse" universe.
Without the restrictions of those other characters, Nate Grey (whose title was called "X-Man," but he really wasn't called that very often in the actual comic book) became one of the most powerful mutants in the Marvel Universe. His telekinesis, especially, was his specialty, as he was able to destroy an entire city in his sleep! He also was able to bend water molecules and practically create actual people! However, he lost most of his powers while opening up a portal to another dimension.
The son of Charles Xavier and Gabrielle Haller, David Haller is one of the most powerful mutants around, limited mostly by his Dissociative identity disorder, which put a drag on his power set. Therefore, while a theoretically "cured" Haller would likely be more powerful than the people ahead of him on this list, his split personalities limit his powers enough that he can be defeated. For instance, the Shadow King was able to overpower him during the "Muir Isle Saga."
For a time, he somewhat had control over his personalities, and could tap into them at will, but after his father was killed, the shock took that ability away from him. Afterwards, he began splitting his powers up among the various personalities that make up his mind. To give an idea of how powerful he could be, at one point he used his powers to actually travel back in time to kill Magneto as a "favor" to his father. Instead, he accidentally ended up killing his father in the past (an act that led to the "Age of Apocalypse").
4 CASSANDRA NOVA
Cassandra Nova is one of the most unusual beings in the Marvel Universe, as she is a mummudrai. Mummudrai are phantom beings that are born in the astral plane whenever a new person is born and typically never come into play in the real world. However, Nova was the mummudrai of Charles Xavier, and his mental powers were so vast that she was able to leech on to his psychic powers and slowly turn herself corporeal. She then became, essentially, the evil twin sister of Charles Xavier.
She was powerful enough to brainwash the entire Shi'ar Imperial Guard (and Lilandra) into having them attack Earth. Ultimately, though, she was defeated by the X-Men, showing that her powers weren't quite at the level of, say, her twin brother (she did manage to possess his body for a time). The X-Men trapped her in a mindless form, but even in that form, she was able to manipulate a powerful telepath like Emma Frost into doing her bidding.
3 SHADOW KING
The Shadow King played a major role in the history of the "X-Men," as he was the first evil mutant that Charles Xavier ever encountered (when going by the name Amahl Farouk). Farouk offered to make Xavier a partner in his criminal empire, but Xavier turned him down. They then underwent a dramatic mental battle on the Astral Plane. Xavier ended up barely destroying Farouk. Later on, Farouk seemed to have survived on the Astral Plane alone and began to possess others.
Later on, though, we learned that Shadow King was never actually Farouk to begin with, but rather a being who has always existed on the astral plane and just possesses people. Farouk was one of his most popular hosts. He has been powerful enough that he was able to possess pretty much every telepath below him on the list, with Charles Xavier being the only person to ever truly defeat him (even there, Xavier often needed the help of others).
2 PROFESSOR X
To get an idea of how powerful Professor Xavier is, there have been multiple times where his innermost evil thoughts became powerful enough on their own that they created separate beings (the first one fought against the X-Men and the Micronauts, and the other one, Onslaught, almost destroyed the entire planet!). That's kind of nuts (it is also kind of nuts what kind of weird innermost thoughts he has, like when he was totally going to make a move on Jean Grey when she was a teenager if he wasn't in a wheelchair).
During the "Dark Phoenix Saga," Xavier's mind was so strong that he was able to temporarily lock down the power of Dark Phoenix (she broke free eventually, but come on, that's still really impressive!). Tragically, Xavier was killed in battle with a Phoenix-possessed Cyclops. His brain was then used by the Red Skull for the last few years.
1 JEAN GREY
Jean Grey, the top choice on this list, is a tricky one, since there are multiple versions of Jean Grey, really. There was the original Jean Grey, then there was the Phoenix, a Cosmic force that took on Jean's form in exchange for saving the lives of Jean's friends, then there was Madelyne Pryor, who is a clone of Jean, and now there is a time-displaced teenaged Jean Grey. We're not counting either of those other beings for this list, but instead just spotlight the main person - Jean Grey.
For years, Jean Grey was definitely one of the most powerful telepaths in the Marvel Universe, maybe top 3 or 4, but then things took a change during Grant Morrison's "New X-Men," when Jean Grey realized that her mutant ability had always been the power to channel the Phoenix Force, so really, she essentially is as powerful as the Phoenix, which makes her one of the most powerful beings in the entire universe. She has even been able to resurrect herself! She is the "White Phoenix of the Crown," the ultimate Phoenix user.
Who do you think is the most powerful telepath in comics? Let us know in the comment section!