Grant Morrison’sarrival on theX-Menin 2001 was a shot in the arm to the classic franchise, and its effects continue to be felt today.Morrison, who to that point had been largely known for their work at DC Comics, was an unlikely choice to helm the destiny of Marvel’s mutants.

Some of Grant Morrison’s biggest DC works includeAnimal Man, Doom Patrol, The InvisiblesandJLA.

Morrison had been in comics for over a decade when they took the helm of the franchise. In that time, they acquired a reputation for grand, cosmic ideas, and theirNew X-Menrun was no different.Morrison’s run continues to exert an influence on the franchise today: here are 10 of the best lingering ideas.

E is for Extinction

10Grant Morrison and Frank Quietly Gave the X-Men One of Their Best Villains

Cassandra Nova Was Professor X’s Dark Twin, Literally

Grant Morrison, in league with longtime collaborator Frank Quietly, kicked off theirNew X-Menrun in style, introducing one of the most chilling villains in Marvel history: Cassandra Nova. Professor X’s evil twin who died in the womb, Nova, managed to survive and has spent a lifetime planning revenge, which she got in the most brutal fashion.

Cassandra Nova has stuck around the Marvel Universe, and is still making life miserable for the X-Men. Her creepy powers and ruthless persona have made her a villain X-Men fans love to hate.Cassandra Nova made such an impressionthat she was chosen to be the primary villain forDeadpool and Wolverine,which brought her to the MCU.

9Professor X’s “Outing” as a Mutant Proved Grant Morrison Meant Business

The Revelation of Professor X’s Mutant Status Leaned Heavily into the X-Men’s Queer Metaphor

Grant Morrison is known for big creative swings, and they approachedNew X-Menwith this mentality, upending certain franchise conventions.One of these was “outing” Professor X as a mutant inNew X-Men#116.Prior, Xavier was known as a fierce advocate for mutant rights, but his own status as one was only rumored before he came out.

Professor X coming out as a mutant to the world at large mirrored the anguish and anxiety queer folks felt at that time, and still do.

One of theX-Menfranchise’s greatest strengths is that it reads as a potent metaphor for outsiders in mainstream society, which includes queer individuals. Professor X coming out as a mutant to the world at large mirrored the anguish and anxiety queer folks felt at that time, and still do. Professor X’s outing added another layer to the queer metaphor.

8Grant Morrison Shook Up the X-Men Dynamic By Adding a Classic Villain to the Roster

Emma Frost Continues to Play a Major Role in the X-Men’s Lives

The best X-Men villains are deep and complex, and none was perhaps more so than Emma Frost, who Morrison brought into the team during their run.Early in Morrison’s run, Professor X reopened the school, and Emma Frost, who was previously associated with the Hellfire Club, joined as an instructor.

Emma immediately shook up the X-Men’s stale dynamic, particularly between Jean and Scott (more on that in a minute). She had to work to earn the team’s trust. Emma became so vital to the X-Men after Morrison departed, and the one-time Hellfire Club leader continues to be a major presence in the team’s lives.

7Cyclops and Jean Grey’s Relationship Came Undone

Emma Frost Broke Up One of the X-Men’s Greatest Couples

The X-Men were no strangers to “soap opera” style drama between its members, and Grant Morrison played this to the hilt in their run.Nowhere was this more apparent than in the fraying of the long-standing relationship between Cyclops and Jean Grey. Long considered one of Marvel’s greatest couples, Morrison introduced infidelity into the mix.

The X-Men were no strangers to “soap opera” style drama between its members, and Grant Morrison played this to the hilt in their run.

Morrison’sNew X-Menrun sawJean Grey become the host of the Phoenixonce more, and sacrifice herself to save existence once again. In one of the most bittersweet moments in X-Men history, Jean forgives Scott for his transgressions, and gives her his blessing to be with Emma Frost. Although Jean and Cyclops get back together, Emma’s shadow lingers.

6Cassandra Nova’s Opening Move Killed Countless Mutants

Genosha Was Considered “Untouchable,” but Grant Morrison Proved Everyone Wrong

Grant Morrison and Frank Quietly hit the ground running when they took over the reins of the X-Men franchise by introducing Cassandra Nova, an equal to Professor X.Nova made a grand impression in her debut, sending special Sentinels to the mutant haven of Genosha, killing countless mutants and devastating the once peaceful island.

X-Men ‘97featured its own version of the Genosha massacre.

Allegedly, the Genosha massacre came about due to an editorial mandate that stated there needed to be fewer mutants in the Marvel Universe. Editorial felt Earth had too many mutants, enough to make the “hunted and scared” aspect of the franchise untenable. Two years after Morrison departed, Marvel releasedHouse of M,which depowered a majority of mutants.

5Grant Morrison Introduced a Smart-Aleck, Punk Version of Professor X

Kid Omega, Quentin Quire, Is One of Marvel’s Most Powerful Psychics

Despite the forward-looking nature of Grant Morrison’s X-Men, it also acknowledged the franchise’s past by having Professor X reopen his school to train the next generation of mutants, including Quentin Quire.An Omega-level psychic on par with Professor X and Jean Grey, Quire had an edge that put him at odds with the faculty.

Just like Cassandra Nova, another character introduced in Morrison’s run, Quentin Quire, or Kid Omega as he sometimes likes to be called, continues to be a presence in theX-Mentitles. Kid Omega is a fan-favorite character, and his growth from immature brat to powerful psychic is one of the most rewarding arcs inX-Menhistory.

4Grant Morrison Canonized An Idea PreviousX-MenComics Only Alluded To

X-MenComics Need to Bring Back the Idea of Secondary Mutations

Secondary mutations, in which a mutant gains additional abilities beyond their regular powers, was an idea previousX-Mencomics hinted at, but Grant Morrison made it official.During theirNew X-Menrun, several mutants, including the Beast and Emma Frost, developed secondary mutations. The Beast turned into a cat-like creature and Emma developed a diamond body.

Secondary mutations hint that mutants are capable of even more than previously thought, which deserves more exploration.

The idea of secondary mutations was a big deal during Morrison’s tenure, but once they left the property, it has seemingly fallen by the wayside. This is a shame, as it was one of the most fascinating developments toarise from Morrison’sNew X-Men.Secondary mutations hint that mutants are capable of even more than previously thought, which deserves more exploration.

3Did Grant Morrison Screw Up Magneto? Depends On Who You Talk To

Morrison’s Controversial Take on Magneto Continues to Inspire Debate

Grant Morrison pulled one of the greatest bait and switches in X-Men history, and it angered fans on different levels. InNew X-Men Annual 2001, they introduced Xorn, a mutant with a “star for a brain.”The peaceful Xorn joined the X-Men, but it was later revealed he was actually Magneto, hopped up on a drug that enhanced mutant powers.

This revelation set off a firestorm of controversy among X-Men fans. Some were upset that Magneto would take mutant “steroids.” These fans felt turning Magneto into a one-dimensional, crazed drug addict undid decades of character development, that had transformed the Master of Magnetism into an anti-hero. Marvel decided to walk back on this revelation (more on that later).

2Just Exactly Who is Xorn Then? Marvel Muddied the Waters Around His Identity

Xorn Was Too Good a Character to Waste, But the Creators Failed Him

Part of the reason fans were angry over the revelation that Magneto was Xorn was because they had grown to like Erick’s alter-ego. As initially portrayed, Xorn had a Zen-like demeanor, and he radiated peacefulness. This made the double-cross later all the more heart-breaking, but it also made Xorn into a cult favorite. What was Marvel to do?

After Morrison departed the X-Men franchise, Marvel decided to retcon Magneto’s time as Xorn. Through a series of increasingly convoluted plot twists, the real Xorn was found, and continues to be a presence in the X-Men’s lives. Xorn also has a twin brother, and during the Krakoan era they were confidantes of Legion.

1Grant Morrison’s X-Men Presaged One of the Team’s Best Eras

The X-Men’s Krakoan Era Recalled the Best of Grant Morrison’s Tenure

Grant Morrison’s time with the X-Men introduced new ideas to the stale franchise. Morrison and their collaborators downplayed the superheroic elements and stressed other aspects of the X-Men. Indeed, most of Morrison’s run reads as high-concept science fiction. Once Morrison left the book, Marvel walked back on a lot of their innovations, resorting to the status quo.

However,Grant Morrison’sX-Men run could be viewed as a dry run for one of the greatest eras in the team’s history: Krakoa. Spearheaded by Jonathan Hickman, theX-Men’sKrakoan period recalled the best of Morrison’s run. Yet rather than be a simple retread, Hickman and their collaborators honored the spirit of Morrison’s era by carrying the franchise in bold new directions.