It's no surprise the What If...? animated series on Disney+ is a hit. Audiences are interested in seeing alternate takes of their favorite Marvel Cinematic Universe (MCU) characters. Needless to say, they have plenty of material to work with.

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This includes the What If comic series that ran in two volumes from the late 1970s to the mid-1990s. Each issue presented a look at a different moment in Marvel Comics history that made a slight turn. Thus, events turned out good or bad. There are even some illustrated stories that are too dark for MCU audiences.

10 What If Captain America Were Revived Today Hits Close To Present Issues

What If vol. 1 #44

The MCU reintroduced Captain America to the modern world at the end of The First Avenger. However, writer Peter Gillis and artist Sal Buscema initially did it in What If #44 from the book's original run. Luckily, it happened during a dark period of U.S. history.

In the story, an unknown person revives the 1950s clones of Steve Rogers and Bucky Barnes to help save 1980s America. However, their intentions are flawed, and they eventually support a fascist regime of villains that puts Jewish people and African Americans into walled ghettos. The original Captain America is discovered, thawed, and sees what his clone has wrought. After defeating him, the hero delivers a stunning speech on what a nation is.

9 What If Spider-Man Had Never Become A Crimefighter Shows An Arrogant Peter

The actor known as Spider-Man

"What if Spider-Man Had Stopped the Burglar Who Killed His Uncle?" isn't dark in its concept. Rather, the story by Gillis and artist Pat Broderick sets a dour tone describing what Peter Parker becomes. When he captures the burglar that killed his Uncle Ben in another universe, he becomes an overnight sensation. As a result, his head gets too big for his mask.

Plus, it changes his universe as a whole. For instance, John Jameson isn't rescued by Spider-Man. Thus, J. Jonah Jameson becomes more vengeful against Peter. At one point, he seeks the star's death and, in turn, also injures other heroes like Daredevil. The elder Jameson even goes insane and perishes at the end of the book.

8 What If Phoenix Had Not Died Gets Incredibly Dark At The End

Phoenix and the X-Men

The original "Dark Phoenix Saga" is sad enough with Jean Grey sacrificing herself. However, the story by Mary Jo Duffy and Jerry Bingham is even darker. Although, it doesn't seem to be the case at the start of issue 27 of What If's first volume.

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Resurrected, Jean returns home with the X-Men to resume her role and romance with Cyclops. However, to quench the hunger of the Phoenix Force, she consumes small stars. When Kitty Pryde confronts her, the Dark Phoenix entity emerges. After killing Kitty,  Jean also eliminates Polaris & Cyclops and mentally incapacitates Professor X. In anger and sadness, Jean destroys Earth then proceeds to engulf the entire universe.

7 What If Invisible Girl Had Died Is Terribly Sad

Reed Richards and Prince Namor

Through both volumes of What If, the Fantastic Four appeared in over a dozen issues. During those stories, the respective writers seemed to enjoy taking a darker look at the team. One moment is in "What If Susan Richard Had Died in Childbirth" from issue 42 of the first volume.

Gillis and artist Ron Frenz tell the story of Reed Richard's attempt to save his wife's through an item from the Negative Zone. However, he, Thing, and Human Torch are taken hostage by Annihilus, and Sue Richards dies. Utterly devastated, Reed returns to the Negative Zone to kill the villain. He does so but also dies in the process.

6 The What If The Beast And Thing Continued To Mutate Stories Are Horror-Based

The Beast and Thing

Writers Tom DeFalco and Alan Weiss presented a pair of horror-laced stories that, in a way, actually came true during Marvel's later decades. However, the continued mutations of the X-Men's Beast and Fantastic Four's Thing weren't nearly as dark. In these tales from issue 37 of What If's first volume, these heroes change so much they begin to lose their faith and humanity.

In "What if The Thing Had Continued To Mutate?" by DeFalco and penciler Arvell Jones, Ben Grimm continues to become a horrific monster due to the effects of MODOK's Virus X. Where this story has a happy ending, "What if The Beast Had Truly Become A Beast?" by Weiss has Hank McCoy truly becoming an animal. With his last vestiges of humanity, he asks Professor X for help. He eventually ends up in the Savage Land to live his remaining days as an animal.

5 What If The Hulk Went Berserk Shows What Happens When He Loses Total Control

The Hulk Goes Berserk

Readers have seen The Hulk go from incredible to savage throughout his history. After all, during John Byrne's short run on The Incredible Hulk in the 1980s, an out-of-control version of the character punched a deer for no reason. Yet, he rarely went absolutely berserk with uncontrolled rage.

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This happened in issue 45 of the first volume of What If. Writer Peter Gillis and artist Ron Wilson describe what would happen if the Hulk completely lost control. It dates back to his origins and the fact he gains a telepathic link to Rick Jones after the gamma bomb explosion. When General Thunderbolt Ross unintentionally kills Rick, the Hulk goes crazy. He ends up killing The Thing and Iron Man before Thor ends up snapping Banner's neck.

4 What If The New X-Men Had Died On Their First Mission Is Dark With A Silver Lining

The Original X-Men

The X-Men and their numerous characters graced over three dozen issues of What If. Most of these appeared at the crux of their popularity in the early 1990s. An example of this is issue nine of the second What If volume.

This story, by Roy Thomas and Rich Buckler, hypothesizes what would have happened if the New X-Men had died on their very first mission— the one where they attempted to rescue the original lineup from Krakoa.

Needless to say, Professor X nearly perishes when he feels the deaths of the other X-Men. When Count Nefaria attacks, The Beast, who was with The Avengers at the time of the original story, puts together a new team of mutants to defeat him. Though the story has dark elements, the ending seems to address a sliver of hope for the team.

3 What If Daredevil Killed The Kingpin Is Darker Than The Original Story

Kingpin

Daredevil's "Born Again" storyline by writer Frank Miller and artist David Mazzucchelli is a dark noir classic. It tells the story of Matt Murdock's downfall and seeming resurrection. What If #2 from the series second volume makes it even darker as it asks "What if Daredevil Had Killed The Kingpin?"

Scripted by Danny Fingeroth and drawn by future Batman artist Greg Capulio (on his first assignment), the story shows Matt triumphing over Kingpin by shooting him square in the head instead of getting beaten himself. His sanity slowing slipping away, he attempts to make things right. In the end, instead of being reborn, he and his girlfriend Karen Paige perish.

2 What If The Fantastic Four Lost The Trial Of Galactus Puts Marvel's First Family In The Bullseye Again

Thing, Reed, Susan, Johnny

The Fantastic Four enters the maw of death once again in "What if The Fantastic Four Had Lost The Trial Of Galactus?" Based on the classic John Byrne story from Fantastic Four #262, this alternate version by Roy Thomas and Greg Capulio doesn't have Reed Richards being acquitted after a last-minute appeal by Galactus. Rather, he's found guilty and immediately executed.

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Seeking vengeance, the remaining members of the team end up returning to the Shi'ar homeworld. Using the Control Rod they decimate the entire planet. Though they admit to their sins they also realize a plot is afoot by Kree agents to destroy Earth via the Omni-Wave Projector. In the end, the rest of the Fantastic Four sacrifice themselves by eliminating the Kree threat.

1 What If Wolverine Was Lord Of The Vampires Kills Off Most Of The Marvel Universe

Dracula Kills Wolverine, Nightcrawler, and Colossus

Wolverine appeared several times throughout the second volume of What If. He became an agent of SHIELD, fought Conan the Barbarian, and killed the Hulk. In issue 24 by Roy Thomas and Tom Morgan, Logan becomes the Lord of Vampires.

It takes place after Dracula kills Storm. From there, he takes the blood of Colossus, Nightcrawler, and Wolverine. However, Logan survives and takes the life of the Lord of Vampires to usurp his title. Soon enough, he and his team of vampire X-Men end up killing most Marvel superheroes. The only one that seems to be able to put up a fight is the Punisher.

NEXT: Marvel: 10 What If Stories That Actually Came True