Marvel has become a pop culture juggernaut because of the movies, but comic fans have always known just how great Marvel can really be. Marvel has put out many stories that can be considered the greatest of all time; amazing tales that have changed the Marvel Universe forever, broadening the characters, and expanding the horizons of those who read them. However, there are also a a lot wonderful stories that many readers have missed.

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These stories are no less influential than the greats, but whether it be because they're older or just not as well known to the average fan, many readers have never given them a chance, which is a tragedy.

10 Secret War Changed The Face Of S.H.I.E.L.D. For Years

Wolverine Secret War Costume Cropped

Secret War, by writer Brian Michael Bendis and artist Gabriele Dell'Otto, was a 2004-2005 mini-series that changed one of the biggest facets of the Marvel Universe: S.H.I.E.L.D. Nick Fury recruited heroes to invade Latveria and take out its new prime minister, Lucia von Bardas, in secret, which would blow up in his face.

Told partly in flashback and partly in the present, this book was one of the opening salvos in Bendis's long term plans for the Marvel Universe, taking Nick Fury off the table and introducing Maria Hill as new S.H.I.E.L.D. director. S.H.I.E.L.D. has evolved a lot over the years, but this book was the beginning of a lot of changes and it's criminally slept on.

9 Kurt Busiek & Mark Bagley's Thunderbolts Is A Classic That Few Younger Fans Have Read

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It's really hard to describe how big writer Kurt Busiek and artist Mark Bagley's Thunderbolts #1 reveal was to someone who wasn't there. The team looked like it was going to just be another generic superhero team but that last page reveal of their true identities changed everything, making them one of the greatest villain teams of all time.

The rest of their run on the book is more of the same, as the Thunderbolts struggled with their new role, gained and lost members, and told some of the best superhero stories of the late 1990s. Busiek's one of '90s Marvel's unsung heroes and Bagley is one of the greatest superhero artists of all time. Together, they made something special.

8 Avengers: Ultron Unlimited Is The Greatest Ultron Story Of All Time

Ultron with the Avengers lying in defeat behind him in Marvel Comics Ultron Unlimited

Speaking of Kurt Busiek, his late '90s Avengers run with George Pérez is an unsung gem, and one of its best stories is Ultron Unlimited. Featuring Ultron committing one of his most heinous acts— the destruction of the country of Slorenia in mere minutes— it's easily the greatest Ultron story ever. Add to that one of the best Avengers rosters of all time, plus Pérez's amazing pencils, and it's a remarkable story.

What makes it so influential is that it helped influence Avengers: Age of Ultron and is probably the last Ultron story that everyone can agree is good. Unfortunately, it's been out of print for over a decade and is as forgotten as the amazing run it came from.

7 Captain America: Operation Rebirth Was Overshadowed By Heroes Reborn

Captain America Operation Rebirth in Marvel Comics

The '90s were not a great time for Captain America. He didn't fit the decade's extreme aesthetic and Marvel kind of didn't know what to do with him. With his book on its last legs, they ended up throwing it to writer Mark Waid and artist Ron Garney, who would put out Captain America: Operation Rebirth— a back to basics tale that pitted Cap against Red Skull with the Cosmic Cube on the line.

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Reaction to the book was positive overall and readers started to come back, but then Marvel announced Heroes Reborn and Waid and Garney's run ended prematurely. This story was an example of Captain America at his best and more people need to check it out.

6 Paul Jenkins & Jae Lee's The Inhumans Should Have Acted As A Blueprint For The Concept

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Marvel historically botched the Inhumans, both in the comics and elsewhere, but the irony is they had the perfect blueprint for them in 1998's The Inhumans by writer Paul Jenkins and artist Jae Lee. Their tale would focus on the characters and what made them tick, instead of trying to make them into an X-Men knock-off.

The book would give Jenkins and Lee a lot of exposure and get them more Marvel jobs, but beyond that, it's just a really good Inhumans story, one that makes it easy to miss the concept. The fact Marvel botched everything about them so badly when they had the answer right there proves that most people at Marvel never even read the story themselves.

5 Fantastic Four #258 Is The Essential Doctor Doom Story

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Writer/artist John Byrne's Fantastic Four is probably one of the greatest comic runs of all time, full of amazing stories that have been forgotten by time. However, one of the best occurs in Fantastic Four #258, a single issue story focusing on Doctor Doom. Calling it the best Doctor Doom story of all time isn't that much of a stretch, and it's one of the first times Doom got such a large spotlight.

The issue really got into his head and did a fantastic job of showing why Doom is one of Marvel's greatest villains. Byrne's run is a treasure trove overall, but this issue is one of it's brightest moments.

4 Doctor Strange: Triumph And Torment Is Well-Known But Not Well-Read

Doctor Strange and Doctor Doom in the comic, Triumph and Torment

For someone who's such a big part of the Marvel Universe, Doctor Strange doesn't have a lot of stand out stories. However, there's one that everybody knows about but isn't nearly as well read as it should be: Writer Roger Stern and artist Mike Mignola's Doctor Strange: Triumph And Torment, which teamed up the Doctors Strange and Doom against Mephisto.

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This story introduced both Doom's magical power and the story of his mother's life, two things which would become integral to the character. It's honestly more of a tale for Doctor Doom than Doctor Strange and it built a lot of back story for Latveria's monarch.

3 Wolverine #48-50 Added More Wrinkles To Wolverine's Time With Weapon X

The cover and two panels from Wolverine #50

Weapon X has always loomed large in Wolverine's life. The sinister agency gave him his adamantium skeleton and forged him into a weapon, with some of the best Wolverine stories being about him dealing with them. Writer Larry Hama and artist Marc Silvestri's Wolverine #48-50 focused on Wolverine searching for more clues to his past and learning even more about the group.

This three issue story would add even more wrinkles to Wolverine's origin, going more in depth on his memory implants and how far Weapon X went to control and manipulate him. It's also just a great Wolverine story from two of the best creators to ever work on the character.

2 The Sentry Introduced One Of The Most Important Marvel Characters Of The 21st Century

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The success of 1998's The Inhumans led to writer Jenkins and artist Lee getting a chance to shine again with 2000's The Sentry. Advertised as the return of a long forgotten Stan Lee creation, The Sentry starred a character that was ostensibly a Marvel version of Superman but would end up far different, eventually becoming a big part of the Marvel Universe.

This inaugural tale did all the heavy lifting, introducing the character's lore and most of his life story and was a classic of turn-of-the-century Marvel.

1 Avengers Forever Cleaned Up Loads Of Complicated Avengers Continuity & Is One Of The Best Avengers Stories Ever

Avengers Forever Captain America Throwing His Shield In The Center

Avengers Forever, by writers Kurt Busiek & Roger Stern and artist Carlos Pacheco, isn't an easy read, but it's a must for any fan of the team. Starring a team of Avengers from the past, present, and future and pitting them against the machinations of Immortus and the Timekeepers, the name of the game with this story is untangling Avengers continuity while telling a great story— and it does both perfectly.

Avengers Forever can be a handful, but it's so very rewarding, pulling readers right in and never letting up. It can seem daunting from the outset but it does a great job of explaining and setting up and is filled with amazing characterization along with killer art.

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