Marvel has been dropping amazing stories for years. There are lots of factors in a great story. Sometimes, it's something quiet, such as game-changing character development. Sometimes it's epic action that fans never forget. One of the best, though, is the big reveal. These moments, when creative teams give up the ghost on a plot development they've been cooking up for months or drop a surprise bomb on readers, can be unforgettable when done right.

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These reveals have been the epitome of the term game-changing, shaking up the status quo and exciting readers in ways they never thought possible.

10 Spider-Man Revealing His Identity To The Public In Civil War #2 Led To Unforeseen Places

Civil War #2 Spider-Man In The Middle Of Team Captain America And Team Iron Man

Civil War #2's reveal, by writer Mark Millar and artist Steve McNiven, is strange in that it's something that readers have always known, but it fits in the game-changing reveal category. At the behest of Iron Man, Spider-Man revealed his identity to the world to persuade more people to support the Superhero Registration Act. This reveal took Spider-Man places no one ever thought it would and changed the characters forever.

No one would have suspected that this reveal would have led to the dissolution of Peter Parker's marriage to Mary Jane in order to save the life of Aunt May. Spider-Man revealing his identity led to a creative renaissance for the character, even if readers have hated the change for years.

9 Hulk #22 Revealed The Identity Of The Red Hulk

Hulk #22 Spider-Man Webbing Red Hulk

The Red Hulk was a big deal in Marvel for a while, cutting a swath through the Marvel Universe. Fans were abuzz at who he was, with speculation running rampant. Hulk #22, by writer Jeph Loeb and artist Ed McGuinness, finally revealed the new Hulk's identity, and Hulk's arch-enemy Thunderbolt Ross was outed as the Red Hulk.

Fans were shocked, as Red Hulk himself had "killed" Ross. It was just an LMD, though, and Red Hulk's actions made a lot more sense. Red Hulk stayed a hot commodity for years to come and even now makes sporadic returns.

8 Excalibur #1 Revealed The Truth Behind An Epic X-Men Moment

Magneto returns in Excalibur (2004) #1

One of the biggest reveals in Grant Morrison's New X-Men was that Magneto had posed as Xorn and attacked the school from within. This would lead to him taking over New York City, getting beat by the X-Men, killing Jean Grey, and finally being beheaded by Wolverine. Excalibur #1, by writer Chris Claremont and artist Aaron Lopresti, turned that on its ear.

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Following Professor X to Genosha as he tried to help the mutants stranded there after its destruction, it was revealed he had an unexpected partner — Magneto. The Morrison reveal was completely undone, as it was instead revealed that Xorn had been Xorn posing as Magneto the whole time.

7 Captain America #6 Revealed The Identity Of The Winter Soldier

Captain America 6 Cropped

Bucky Barnes has changed a lot over the years, and the biggest changes involved his death, resurrection, and reveal as the Winter Soldier. That last reveal happened in Captain America #6, by writer Ed Brubaker and artist Steve Epting. The team had been building up the mysterious new assassin the previous issues, and the reveal that Winter Soldier was Bucky was completely unexpected.

The Captain America mythos was changed forever with this moment. The return of Bucky overturned one of the conventional bits of Marvel wisdom — Bucky stayed dead — and led to some of the best Captain America stories ever.

6 Fantastic Four #286 Revealed The Truth Of "The Dark Phoenix Saga"

An image of Jean Grey appearing to the Fantastic Four after her resurrection

"The Dark Phoenix Saga" is one of the X-Men's greatest tales, ending with Jean Grey killing herself in order to keep the Dark Phoenix from devouring the universe. Fantastic Four #286, by writers John Byrne and Chris Claremont with art by Byrne and Jackson Guice, changed all of that. It revealed that Jean Grey had been held in a cocoon at the bottom of Jamaica Bay and was never the Phoenix.

This brought Jean Grey back to life, giving the X-Men back one of their icons. It also changed the impact of "The Dark Phoenix Saga" forever, for better and for worse. It was a major league reveal that would never work today, as it would have been revealed months earlier to gin up fan interest.

5 X-Men #54 Revealed The Identity Of Onslaught

X-Men #54 Onslaught Looms Over The X-Men

Onslaught was a huge deal in mid-90s Marvel, with the character being teased immediately after The Age Of Apocalypse ended. Onslaught's threat was built up in the X-Men books, but fans hadn't even gotten a glimpse of what he really looked like. That finally happened in X-Men #54, by writer Mark Waid and artist Andy Kubert, when the entity reached out to Jean Grey.

The two clashed on the Astral Plane, with Onslaught handily beating Grey. However, she made a shocking discovery during this battle: Onslaught was Professor X. This would kick the entire Onslaught story into high gear and have massive repercussions for the next few years of X-Men books.

4 The Clone Saga Kept The Reveals Coming

Spider-Man Scarlet Spider Clone Saga

The Clone Saga is one of Spider-Man's most infamous stories and was a game-changer itself in many ways. One of the keys to this was just how many reveals there were. Starting with the return of clone Ben Reilly, it felt like there was a big reveal every couple of months until it was finally "revealed" that Reilly was the one true Spider-Man.

Of course, this was undone as it was eventually revealed that Peter was the real deal, and the whole thing was a plan by the returned to life Green Goblin. This last one was the biggest and would have a huge effect on Marvel in the years to come.

3 New Avengers #31 Kicked Off The Build-Up To Secret Invasion

New Avengers 31 Elektra Is Killed

Secret Invasion was one of the biggest Marvel stories of the '00s, a crown jewels of writer Brian Michael Bendis's Avengers run. It was all kicked off by New Avengers #31, written by Bendis with art by Leinil Yu. On the run from Iron Man in the post-Superhero Registration Act Marvel Universe, the New Avengers went to Japan to retrieve their friend Echo, and things got crazy.

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Battling the Hand, the team was in dire straits when Echo went head to head with the Hand's new leader Elektra Natchios. Echo was able to defeat her, seemingly killing the former hero. Upon death, it was revealed Elektra was a Skrull. This revelation set things on their inevitable course to Secret Invasion.

2 Wolverine #75 Changed Wolverine For Years To Come

Wolverine 75 Wolverine's Bone Claw Powers

X-Men #25 saw Magneto remove Wolverine's adamantium, but that wasn't the end of the story. Wolverine #75, by writer Larry Hama and artist Adam Kubert, was the next chapter. After fighting to survive his horrific injuries, Wolverine went into the Danger Room at the X-Mansion to prove he could still hang with the team. When he tried to pop his claws, bone claws ripped through his skin.

For years, everyone thought Wolverine's claws were pure adamantium, but this issue revealed otherwise. It set the underrated bone claw era of Wolverine into motion and changed the way readers looked at Wolverine for the rest of the '90s.

1 House Of X/Powers Of X Was Full Of Reveals That Changed The X-Men Forever

House Of X Powers Of X

Marvel had been shafting the X-Men because Fox owned the film rights for years. When parent company Disney bought Fox, all of that changed, and House Of X/Powers Of X, by writer Jonathan Hickman and artists Pepe Larraz and R.B. Silva, changed everything forever. The two books that are one story were built entirely around massive revelations that changed recast the X-Men status quo.

From the establishment of the nation of Krakoa to Moira MacTaggert's mutant status to the existence of the Orchis Initiative to the secret of Krakoan resurrection to the tragedies of every future for mutants, House Of X/Powers Of X threw reveal after reveal at readers.

NEXT: 10 Times The X-Men Changed The Marvel Universe