Grant Morrison is one of the greatest writers in comics. In their decades-spanning career, they've worked on all of DC's major characters, as well as multiple creator-owned projects. They've also worked at Marvel, although their footprint at the publisher isn't as big. Morrison spent most of their stint at Marvel on New X-Men, a book that brought the hidebound franchise kicking and screaming into the new millennium, as well as some miniseries.

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Morrison's big imagination was perfect for Marvel, and they created some amazing stories. If Marvel editorial hadn't run them off, it boggles the mind what could have been judging from the quality of what they did.

10 Marvel Boy Was Morrison's Inaugural Marvel Story

Marvel Boy

For a lot of diehard Marvel fans, those who didn't leave the House of Ideas, 2000's Marvel Boy, with art by J.G. Jones, was their first time encountering the gonzo imagination of Morrison. The book told the story of Noh-Varr, a genetically modified Kree soldier from an alternate universe. His multiverse traveling ship is shot down by Dr. Midas, its crew killed, and him captured.

He escapes, and it gets crazier from there. Morrison showed Marvel readers what they could do in the Marvel sandbox, taking familiar concepts and going nuts with them. Jones's art is wonderful as well, bringing Morrison's massive concepts to life. As far as opening salvos go, Marvel Boy is potent.

9 "Germ-Free Generation" Pits The X-Men Against John Sublime

Angel Salvatore Cropped

"Germ-Free Generation" was a sign of things to come in New X-Men. Joined by artists Ethan Van Sciver and Igor Kordey, it introduced the U-Men, a group of humans who vivisect mutant in order to gain powers themselves. Led by pseudo self-help guru John Sublime, they set their sights on the school.

"Germ-Free Generation" gets a bad rep because of Kordey's art, a consequence of Quitely's backup artist Van Sciver being even slower than him and Kordey's writing and drawing of Cable at the same time. The art is often rough, but the story itself is great, introducing important characters like Sublime and Angel Salvadore. The U-Men are also a great concept, and the story itself is pretty great.

8 "Riot At Xavier's" Was Bratty Morrison Fun

Quentin Quire and his gang

One of the fun things about Morrison's writing is how well they capture petulant teenagers. New X-Men gave them lots of opportunities for this, as they brought back the school concept in a big way. "Riot At Xavier's," with art by Frank Quitely, introduced readers to the Omega Gang, a group of angry students who decide to fight the power, led by Quintin Quire.

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The young mutants attack the school on its first open house, causing chaos, forcing the X-Men to protect the innocent and deal with these powerful students. It's a great little four-issue story, introduces readers to Quintin Quire and Glob Herman, and features Quitely's last art on the book.

7 "Murder At The Mansion" Introduces A Big Mystery To The Book

A cover image from New X-Men's Murder At The Mansion from Marvel Comics

Morrison brought Emma Frost into the X-Men and made her into one of the franchise's beloved characters. "Murder At The Mansion," with art by Phil Jimenez, is Emma-centric, taking place after Jean discovers her psychic affair with Cyclops. Emma ends up shattered in her diamond form, and the mansion is put on lockdown, with everyone a subject.

Morrison digs deep into Emma with this story, getting more into her back story while propelling the book forward towards its inevitable last few chapters. Jimenez is a frequent Morrison collaborator and knocks it out of the park, as usual, making this story something special and integral for any Emma Frost fans.

6 "Imperial" Pits The X-Men Against Cassandra Nova With The Power Of The Shi'Ar Empire Behind Her

Charles Xavier Killing Cassandra Nova In Womb

Morrison created Cassandra Nova, one of the X-Men's most dangerous villains, and built her legend expertly. "Imperial," with art by Ethan Van Sciver, Frank Quitely, and Igor Kordey, continued that story, as the Cassandra possessed Xavier returned to Earth with the Shi'Ar Imperial Guard under her thrall. Facing a terrible force with students to protect, the X-Men lay a cunning trap for her.

"Imperial" is Morrison doing big X-Men sci-fi in their own inimitable way, and it's amazing. A stand-out is the silent issue where Jean and Emma enter into the wrecked mind of Professor X in Nova's body to learn her origins. It closes out the Cassandra Nova plot line expertly.

5 "Assault On Weapon Plus" Is An Action Epic

Assault On Weapon Plus from Marvel Comics featuring Wolverine and Fantomex.

Wolverine doesn't get a lot of spotlight in New X-Men, but it's always great when he does. "Assault On Weapon Plus," with art by Chris Bachalo, is a perfect example of that. After the events with the riot and the attack on Emma, Cyclops leaves the school, and Wolverine hunts him down at the Hellfire Club, enlisting him for a mission with Fantomex to the World, home of Weapon Plus.

Wolverine and Cyclops are the ultimate odd couple, and Morrison plays that up wonderfully. Add in the wild card that is Fantomex, and this story is a lot of fun, on top of being an action-packed banger. Bachalo's detailed, quirky art style is just what the doctor ordered for this story and goes very well with Morrison's scripting.

4 "Here Comes Tomorrow" Puts The Bow On Morrison's New X-Men

X-Men Here Comes Tomorrow 1

Marvel is known for their dark alternate futures, and that goes doubly so for the X-Men. Morrison threw their hat into that ring with their last New X-Men epic, "Here Comes Tomorrow," with art by Marc Silvestri. Set a hundred years in the future, it sees the X-Men trying to retrieve the Phoenix Egg from the Beast in a world on its way out.

Morrison does a fantastic job creating a dystopian X-Men future. They close out all of their major plots and give readers a glimpse of a world gone wrong. Silverstri turns in some of the best art of his long career, and this story is a wonderful coda to Morrison's Marvel tenure.

3 "E Is For Extinction" Is Where It All Starts

New X-Men

As far as mission statements got, Morrison makes a great one with "E Is For Extinction," with art by Frank Quitely. Right off the bat, it felt completely different from any other X-Men story ever. As the X-Men discover the extinction gene in humanity, a new threat to mutant-kind rears its head- Cassandra Nova.

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Morrison's run was revolutionary, and this story did a remarkable job of setting that up right out of the gate. New concepts, secondary mutations, new costumes, and bringing in Emma Frost were the icing on the cake, and Morrison threw in big shocking moments like the destruction of Genosha. They jarred the reader from the start, and it's still a perfect three-issue story.

2 "Planet X" Was Morrison's Final Word On Magneto

New X-Men - Magneto Attacks New York

Magneto was seemingly barely there for most of Morrison's run but played a much more significant role than anyone imagined. That was revealed in "Planet X," with art by Phil Jimenez. Magneto springs his trap on the X-Men, destroys the Mansion, and takes over Manhattan, leaving the heroes in dire straits with little hope of defeating him.

Magneto had been built up as a noble character for years, but post-9/11, Morrison wanted to show him for the deluded terrorist he was. "Planet X" does that expertly, and it's also just an amazing X-Men story, seeing the team come from behind for the win. Expertly rendered by Jimenez, Marvel eventually retconned most of it, but that doesn't take away from how great it truly is.

1 New X-Men #132 Is A Haunting Ghost Story In The Graveyard Of Genosha

New X-men 132

New X-men #132, with art by Phil Jimenez, isn't some big, world-ending story. In fact, it's a quiet ghost story set in the ruins of Genosha. The destruction of the first mutant nation was a traumatic day for mutantkind, and a group of mutants still living there call in the X-Men to help them deal with a haunting.

Morrison and Jimenez team up for a great little story, one that plays on the open wounds of the mutant race. It features Quicksilver and Polaris dealing with their father's death in their own ways. It's an amazing single story, a rarity in today's comic industry.

NEXT: Supergods: 10 Best Insights Into Grant Morrison's Book About Superheroes