There are a lot of X-Men. With over 50 years of stories spread across an even higher number of ongoing series, hundreds of characters have emerged from this one corner of the Marvel Universe and become fan favorites. The X-Men and their assorted spinoff teams have produced an incredible number of lead and supporting characters with extensive histories -- but the universe as of late has felt smaller than normal.

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Over the past few years, a select group of X-characters have risen in prominence. An equal mix of old favorites (Storm, Nightcrawler, Psylocke) and new mainstays (Oya, Magik, the time-displaced original team) have consistently rounded out the casts of the various X-Books since they emerged from "Avengers vs. X-Men" in 2012. Longtime X-readers may feel like something's been missing from the line for the past few years, and after doing the research, that "something" might just be a number of important supporting characters that have taken a backseat to the currently prominent core group.

To figure out which mutants have slipped back into publishing limbo, we narrowed down the list of every X-Character to just those with over 100 appearances on the Marvel Database and the ones currently canonically living. That part's important; there are a surprising number of X-Characters that have stayed dead and therefore not had a current canonical appearance in decades (like Mastermind, Rusty Collins and Jean Grey). But they're dead, so we kinda know what they're up to (being dead). Next, the living characters' last appearances were examined, overlooking recent appearances that were either non-canonical or flashbacks. Non-speaking cameos were also overlooked, since fans of a character certainly want to see their fave do more than appear in a crowd shot. The last time a character spoke -- even a line as short as a word -- counts as their last appearance. And this list starts with characters that have been missing for a minimum of two years. With all that research concluded, here are the 21 most prominent X-Men that have been missing in action for a surprisingly long time.

21 CHAMBER





Last Speaking Appearance: "Nightcrawler" #4 (September 2014)

The Generation X kids have generally had a rough go of it, and this list starts off with three alumni of that team/series. Jonothon Starsmore, codenamed Chamber due to the psionic energy furnace erupting from his chest, started out as a mainstay member of Generation X in 1994. Initially sullen and somewhat goth, Chamber grew over the years into a capable leader and unlikely X-Man. Like a number of supporting X-Characters that found themselves without a series in the early 2000s, his forward trajectory was halted by M-Day. The event, part of the fallout from the Marvel crossover "House of M," robbed plenty of mutants of their powers; Chamber got through the '00s with number of odd retcons (he's a descendant of Apocalypse) only to end up back at square one: missing half his face. Jason Aaron brought Chamber back into the fold as a teacher at the Jean Grey School, a role that continued through to the recent "X-Men: Legacy" series written by Si Spurrier. And that's pretty much where we last saw Jonothan, as a teacher running into action in the pages of Chris Claremont's "Nightcrawler" series two years ago.

20 HUSK





Last Speaking Appearance: "Nightcrawler" #4 (September 2014)

Paige Guthrie is another Generation X alum that's fallen back into limbo. As the younger sister of the New Mutant turned X-Man turned Avenger Cannonball, Paige's ties with the X-Men go back further than most of her Massachusetts Academy peers. Despite her kinda off-putting power (she can rip off her skin to reveal a different form underneath), Husk studied hard as a member of Gen X and strived to lead the team. Her determination eventually earned her a spot on the X-Men, where she began a relationship with the considerably older Angel. Like Chamber, Husk found herself working at the Jean Grey School as a teacher. Her slow-burning storyline in "Wolverine and the X-Men" involved her falling in love with Toad and defecting to the Hellfire Club, two actions that were the result of a secondary mutation that caused her mind to alter with every new form she took. We last saw Paige in the same "Nightcrawler" issue as Chamber, where she was back on staff at the JGS.

19 BANSHEE





Last Speaking Appearance: "Uncanny Avengers" #20 (July 2014)

The former co-headmaster of "Generation X's" Massachusetts Academy has also disappeared over the past few years. A legendary X-Man, the sonic-screamer Banshee was a member of the second generation team that also included Nightcrawler, Wolverine, Storm and Colossus. The Irish superhero served as a member for many years before retiring to a quiet (for a superhero) life with his partner Moira MacTaggert. Sean Cassidy came out of retirement to help instruct the Generation X class of mutants, and years after that sacrificed himself in an attempt to save the passengers of an airplane in "X-Men: Deadly Genesis." True to the superhero genre, Banshee came back from the dead three times after that; his resurrections in the "Necrosha" and "Chaos War" storylines didn't take, but his return as one of the Apocalypse Twins' Horsemen of Death in Rick Remender's "Uncanny Avengers" opus did. The storyline ended with Banshee resurrected but fighting the influence of Apocalypse's Death Seed. He's now been fighting that influence for just over two years, off-panel.

18 SURGE





Last Speaking Appearance: "X-Men" #13 (June 2014)

The "New X-Men" class of mutants have had just as much trouble staying in the spotlight as the "Generation X" kids have. Surge, one of the early breakout characters from this generation of X-students, is an example of that. After initially not being able to control her electricity absorption power, the X-Men created gauntlets for her that got her powers under control and added to her recognizability. She grew into the leadership role of the New X-Men team and, following the end of that series, has slipped into the background. Her blue hair and gauntlets made her a popular character for artists to toss into the background at the Jean Grey School, so readers at least knew she kept up with her studies. But to actually see Surge speaking, you have to go back to Brian Wood's "X-Men" run just over two years ago where she was seen playing baseball with the rest of the students.

17 BLINDFOLD





Last Speaking Appearance: "X-Men: Legacy" #24 (April 2014)

Ruth Aldine has the rare distinction of being one of a few lasting X-Characters to be created by Joss Whedon. Following Ruth Aldine's minor role in "Astonishing X-Men," writers put her psionic and precognitive abilities to use in teen titles like "New X-Men" and "Young X-Men." Following the conclusion of those student-centric series, she regularly popped up in issues of the main X-Men team books, usually delivering ominous portents. Like Surge (and the other "New X-Men" character on this list), her unique design made her a character that artists would toss in as a non-speaking cameo. Blindfold's recent disappearance came after her most exposure ever as the quasi co-lead of "X-Men: Legacy."

16 STRONG GUY





Last Speaking Appearance: "Thunderbolts" #22 (April 2014)

Here's a strange sentence for any '90s "X-Factor" fans that haven't kept up with Marvel's merry mutants: Strong Guy is the king of Hell. Yes, Guido Carosella, X-Factor's ridiculously proportioned jokester, stole Mephisto's job. Despite humble beginnings as Lila Cheney's bodyguard, Strong Guy defied expectations and became a consistent supporting player in the X-Men line. He provided muscle for two different long-lasting "X-Factor" runs and ended up possessing a surprising amount of depth. Guido ended up with his unlikely gig after meddling with a demigod's quest to murder every Hell Lord and assume the mantle as King of Hell. Guido killed the demigod Tier and received the reward. Strong Guy was last seen in an issue of Charles Soule's "Thunderbolts" run wherein he turned down an offer to return to Earth, instead choosing to remain in Hell and search for his soul. He's presumably still down there looking for it two years later.

15 SPIRAL





Last Speaking Appearance: "Uncanny X-Force" #17 (March 2014)

The end of an ongoing series sometimes means that those characters will go back in the toy chest, just waiting for a future writer to dig them out again. The end of "Uncanny X-Force" in early 2014 put two characters back in storage: Spiral and Bishop. As the villain Mojo's former enforcer and general all-around antagonist, the teleporting Spiral was always an unlikely choice for an X-Team member. But Spiral became just that in Sam Humphries' "X-Force" run, serving right alongside heroes (like Psylocke) that she had previously tormented in unspeakable ways. Spiral's moment in the spotlight came after almost two decades in the X-Mythos, usually operating as a member of villain teams like Freedom Force and the Sisterhood. But since "Uncanny X-Force" ended, Spiral has yet to dance her way back into any new comic.

14 BISHOP





Last Speaking Appearance: "Uncanny X-Force" #17 (March 2014)

Bishop's journey over the past decade is a tragic one. Originally introduced as a time-traveler from the far future determined to thwart the assassination of the X-Men by one of their own, the militaristic mutant found a new purpose in life as a member of the X-Men -- the very heroes he grew up idolizing. But Bishop's ties with the X-Men were broken with the birth of a baby named Hope; Bishop knew her to be the mutant responsible for the horrific conditions of his home timeline. When fellow time-traveling mutant Cable took Hope under his care, an enraged Bishop hunted the father/adoptive-daughter duo across the timestream. Bishop was eventually cured of his madness, accepted his deadly mistakes, and returned to the present where he slowly earned back the trust of some of the X-Men he betrayed. Bishop's last appearance saw him make tense amends with Cable and the now teenaged Hope, but we've yet to see Bishop's next step.

13 DANI MOONSTAR





Last Speaking Appearance: "Fearless Defenders" #12 (February 2014)

Dani Moonstar is a big deal. If you came of age in the '80s, then you know Moonstar as the strong-willed and fiercely independent co-leader of the New Mutants. After leading the first X-Men spinoff book in the '80s, Dani slipped into the background for much of the '90s; that decade gave her the brain-frying psionic arrows that she would come to be known for, but her appearances were few and far between until her short-lived stint in "X-Force." Like Chamber, Dani also lost her powers on M-Day; unlike Chamber, she never got them back. Still, this human superhero returned as a major character in a new "New Mutants" series and followed that up with a major role in "Fearless Defenders." But aside from some flashback appearances, Dani's been missing since the end of "Fearless Defenders" over two years ago.

12 MAGMA





Last Speaking Appearance: "Fearless Defenders" #11 (January 2014)

While Magma wasn't as much of a New Mutants mainstay as the aforementioned Dani Moonstar, she still wracked up a number of appearances during her '80s heyday at Marvel Comics. Gifted with geothermal powers that allow her to manipulate tectonic plates and manipulate lava, Magma's molten form has become one of the more recognizable ones in X-Comics. And after taking much of the '90s off, Amara Aquilla came back in the pages of "X-Treme X-Men" and "Young X-Men" in the early '00s. The revived "New Mutants" series gave her the most consistent exposure she's enjoyed since the '80s, but the end of that series in 2012 also ended her time in the spotlight. She's only appeared in one issue of "Fearless Defenders" (alongside her old pal Dani) in the last four years.

11 X-MAN





Last Speaking Appearance: "Fearless Defenders" #9 (November 2013)

The third of three characters whose last appearances were part of a "New Mutants"/"Fearless Defenders" combo, X-Man (AKA Nate Grey) proved to have a surprising amount of staying power. Originally introduced as the "Age of Apocalypse's" answer to Cable, this artificially created genetic combination of an alternate reality's Jean Grey and Scott Summers survived the destruction of his home dimension and landed in the main Marvel universe where he remained the lead of his own book for 75 issues. His appearances became infrequent for much of the '00s, until he added his massive psionic abilities to the might of the reformed New Mutants team. Nate remained a member of the team until their most recent end, and even struck up a relationship with Dani Moonstar. His last appearance was in late 2013 in an issue focused on the romantic partners of "Fearless Defenders'" heroines.

10 SIRYN





Last Speaking Appearance: "X-Factor" #262 (November 2013)

Yep, there's a father/daughter duo on this list: Banshee and Siryn. Neither Sean Cassidy nor Theresa Cassidy have been seen in years, although Siryn disappeared from the line before learning of her father's return from the dead. Originally a reformed criminal serving on the seldom-seen Muir Island contingent of X-Men, Siryn joined the major leagues when she hooked up with Cable's X-Force team very early in that series' run. Siryn stayed with "X-Force" for much of the '90s, eventually earning the leadership role. Terry then enjoyed a very, very lengthy run in "X-Factor," a series that (as the next few entries will show) gave a home to a number of prominent X-Team players. As she possesses the same powers as her father, she eventually took on his codename to honor him. But that's not the last codename Siryn/Banshee used; she's currently the Marvel Universe's Morrigan, a Celtic god. Theresa sacrificed her humanity in exchange with the previous Morrigan as part of a deal to restore her X-Factor teammate Polaris' sanity. The new Morrigan was last seen in "X-Factor's" last issue

9 MULTIPLE MAN





Last Speaking Appearance: "X-Factor" #262 (November 2013)

After starting with Siryn, we're now firmly in the "X-Factor" phase of this list. Including Strong Guy, who got bumped up because of that "Thunderbolts" appearance, "X-Factor" characters make up a third of this list. The end of "X-Factor," which was led by Multiple Man for all of its 100+ issues, really closed the book on a lot of mutants. After playing the role of comic relief in the '90s "X-Factor" series, Jamie Madrox came back as a fully-formed leading man in Peter David's long-running noir/comedy/drama ensemble book. The series even went into Madrox's multiplication power and established that he's part of a subset of humanity that predates mutants. As the book's lead, Jamie became inextricably tied to it -- a point that's proven by the fact that he hasn't appeared in a speaking role in the three years since "X-Factor" ended.

8 LAYLA MILLER





Last Speaking Appearance: "X-Factor" #262 (November 2013)

Originally introduced in the "House of M" event, Layla Miller became much more fleshed out as an integral part of "X-Factor" after the event concluded. She also grew up during the series' run, although that mostly took place behind the scenes in a far-flung future. Miller's power also expanded from vaguely "knowing stuff" to being able to resurrect the dead, although doing so robbed the returnee of a soul. Yep, Strong Guy found that out the hard way (though if there's a chance he can find his own soul while in Hell, others could follow suit). But while "X-Factor" ended with Guido in Hell and Siryn a Celtic god, it ended quietly for Madrox and Miller. They retired to a farm together and, when last we saw her, Layla was expecting a child. If comic time passed like real time, that child would be a toddler now.

7 SHATTERSTAR





Last Speaking Appearance: "X-Factor" #259 (September 2013)

Rob Liefeld co-created the ponytail-sporting and sword-slinging Shatterstar as quite possibly the most '90s character ever (not that we're complaining), but he enjoyed a notable stretch of character development as a member of Peter David's long-running "X-Factor" series. David established Shatterstar as bisexual and polyamorous, developments that had been left as subtext by previous writers. He explored 'Star's relationship with teammate Rictor and, in an appropriately confusing origin story issue, established that Longshot is both Shatterstar's father and son and tied up a half dozen dangling plot threads from over 20 years of continuity. Still with us? But Shatterstar's origin story would be his most recent appearance; after getting his history sorted out, he hasn't been seen again.

6 RICTOR





Last Speaking Appearance: "X-Factor" #259 (September 2013)

And now it's time to meet the other half of "X-Factor's" power couple, Rictor. Julio Esteban Richter got his start as a ward of X-Factor and, a little later, a member of the New Mutants. Like many of the New Mutants, Rictor eventually found his way to "X-Force," where he spent most of the '90s and met his future boyfriend Shatterstar. M-Day took away Rictor's earthquake-making powers, a development that nearly drove him to suicide; he later joined Madrox's X-Factor Investigations instead and stayed with the team for much of its long run. He eventually got his powers back, too, making him more ready than ever to serve on a superhero team -- and then Rictor (along with Shatterstar) disappeared when "X-Factor" ended in 2013.

5 WOLFSBANE





Last Speaking Appearance: "X-Factor" #258 (August 2013)

The final "X-Factor" member, on this list, Rahne Sinclair's association with the X-Men is as long as Dani Moonstar's; both of them were original members of the New Mutants back in the '80s. The mutant lycanthrope ended up a member of the government-sponsored X-Factor team in the early '90s, migrated to Excalibur in the late '90s, and then resurfaced as a teacher in the early '00s "New Mutants" book. IN a word: Wolfsbane's been everywhere. She then got consistent exposure as a member of Wolverine's black ops X-Force team, with stints at X-Factor Investigations bookending that. And that's where Rahne was last seen, in "X-Factor" in summer 2013 having taken on the role of deaconess at a church in Vermont, never to be heard from again.

4 DUST





Last Speaking Appearance: "Scarlet Spider" #17 (July 2013)

Sooraya Qadir is one of the many mutants that Grant Morrison introduced during his landmark run on "New X-Men" at the start of the 21st Century. As one of the first Muslim superheroes, Dust's addition to the X-Men was a positive step toward inclusion and diversity, as was her addition to subsequent teenage X-Men teams following the end of Grant Morrison's initial run. She was a part of both the New X-Men and Young X-Men squads, and has appeared in a number of other X-Men comics as a member of the student body. Like Surge and Blindfold, Dust still appears in crowd shots of students, but it's been a while since she actually had a line of dialogue. The last time Dust spoke was in "Scarlet Spider" #17 over three years ago, when she answered a question with the word "no."

3 SAGE





Last Speaking Appearance: "X-Treme X-Men" #13 (June 2013)

Thanks to a retcon more than two decades after her debut in 1980, Tessa's ties with Professor X were established as existing even before the creation of the original team. Gifted with what's described as a "computer brain," Sage served as a spy for Xavier within the Hellfire Club's ranks for years before finally revealing her true allegiance. When she did, she became an official X-Man on Chris Claremont's X-Treme X-Men team. Following that run and a brief stint in "Uncanny X-Men," though, Sage slipped back into the shadows until Greg Pak reintroduced her in the pages of his "X-Treme X-Men" series (which shared the same name but not the same team mandate). But once that series concluded in 2013, Tessa once again disappeared -- perhaps waiting for another writer to launch a series called "X-Treme X-Men."





Last Speaking Appearance: "New Mutants" #50 (December 2012)

Basically this entry is for two characters named Blink: the original Clarice Ferguson who spent a solid 15 years dead in the main Marvel U, and the alt reality "Age of Apocalypse" version of the character that fans fell in love with in the "Exiles" ongoing in the interim. The teleporter known as Blink sacrificed her life to save the Generation X recruits just two issues after her debut in 1994. Not letting a good character design go to waste, a different version of her was used heavily in the "AoA" storyline and then carried over to the "Exiles" ongoing, which lasted for over a hundred issues and ended in 2009. When "Exiles" ended, the original Blink was resurrected and ended up joining the cast of the relaunched "New Mutants" series where she starred alongside Moonstar, Magma and Nate Grey. But with that book's end in 2012 also came yet another end for Blink.