Since the time that we could lift our heads to read a book or watch television, we have always had a fascination with superheroes.  The ability to fly or to have super strength, or to run very fast has forever preserved a childlike quality in all of us.  So, even as adults, we get excited when we hear that one of our favorite heroes is going to grace the silver screen.  There is an image ingrained in our minds who should portray our beloved adolescent champions.

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The Marvel Cinematic Universe has been at the forefront of bringing these characters to life.  For the most part, Marvel's casting has been spot one.  But there have been times when fans have wondered, "what if."

So here is a list of ten major casting rumors we wish were true:

Shailene Woodley As Spider-Woman

Now that we have several versions of Spider-Man, it is only fair that we have at least one version of Spider-Woman as part of the MCU.  Spider-Woman?  Yes, Spider-Woman. Jessica Drew, who at a young age, was injected with an experimental serum base on irradiated spider's blood by her father to save her life because she became deathly ill from months of uranium exposure.

Who better than Divergent actress Shailene Woodley to donned the mask and webbed wings. Ironically, Woodley was initially cast as Mary Jane Watson before here scenes were cut in The Amazing Spider-Man 2.

Viggo Mortensen As Doctor Doom

Doctor Doom has been played by both Tobby Kebbell in 2015 and Julian McMahon in 2005. How would fans react to Viggo Mortensen as Victor Von Doom? Already a cinematic fan favorite for his role as Aragon of The Lord of the Rings trilogy, it would be interesting to see him in a different role as the villain.

It seems that Mortensen has been a favorite of Marvel executives for years to play a vital role in the MCU. It would have been nice, but the original project was scrapped.

Rachel McAdams As Black Cat

Sherlock Holmes and Mean Girls actress, Rachel McAdams was rumored to play the "bad luck" temptress Black Cat in Spider-Man 4.  It is a compelling thought to witness Adams as Felicia Hardy, the daughter of a world-renowned cat burglar.

After a traumatic incident in college, Hardy took matters into her own hands. She trained herself in various fighting styles and acrobatics wearing a black suit and following her father's footsteps as a sophisticated thief.

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But this rumor is just that, hearsay. McAdam's name has been added to a list of actresses from Ann Hathaway to Julia Stiles.

Harry Styles As Nova

Marvel executives were looking at a 20- something actor who played in Christopher Nolan's 2017 movie Dunkirk to play the Nova character, Richard Rider. The rumor seems to be leaning towards Harry Styles of the singing group, One Direction. Styles both young and talented seems to be a great choice.

Fans' favorite Nova, a member of the intergalactic police force, Nova Corps, who has superhuman strength, flight, and the ability to resist injury, is planned for MCU phase 5.

But the date is still sketchy. Director Joe Russo of Avengers: Endgame pulled the legs of many marvel enthusiasts by declaring that Nova was in the background of the final battle scene. But, of course, this was not true.

John Krasinski and Emily Blunt As Reed Richards and Sue Storm

John Krasinski and his wife Emily Blunt have been rumored to be the next Mr. Fantastic, Reed Richards, and The Invisible Woman, Sue Storm, making their MCU debut in Ant-Man 3. Nothing has been confirmed, but it is delightful speculation to see the stars of A Quiet Place and A Quiet Place 2 make some noise in the Marvel Cinematic Universe.

Krasinski states that he is a fan of Marvel and would not object to the role. But his wife has kept all things "quiet" directing rumors to Marvel executives to confirm or deny.

Matt Damon As Kraven The Hunter

Sergei Karvinoff, or as comic fans know him, Kraven The Hunter is a demented big game hunter who is out to prove that he is the most prominent hunter of them all by capturing our friendly neighborhood Spider-Man. He bears a lion's mane on his shoulders with wild game teeth around his waist. It would be intriguing to see Jason Bourne's Matt Damon take on this role.

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Damon would have to bulk up a bit and wear skin-tight leopard pants, but once he grows his hair out, he would be a dead ringer. Although this is merely fans' suggestions, The Marvel Cinematic Universe would not be disappointed.

Zac Efron As Adam Warlock

Who other than Zac Efron?  Cocky and easy on the eyes for the fan base. MCU loyalist chant his name like a prizefighter, even adding his likeness to a fictitious Guardians of the Galaxy Vol. 3 poster. Yes, the star of Disney's High School Musical is a satisfying choice. Adam Warlock, the soul capture of other beings (with the help of the Soul Gem) with superhuman strength, speed, durability, stamina, and agility with the ability to fly. He can manipulate cosmic energy projection for recuperation.

At the end of Guardians of the Galaxy Vol. 2, it was hinted that Adam Warlock would appear in the next installment of the franchise. Efron playing Adam Warlock is a rumor solely created by fans. It will be a while before James Gunn starts filming Guardians of the Galaxy Vol. 3, so fans have to keep the chanting down to a mere hum.

Dwayne Johnson As Namor

dwayne johnson

What is a MCU casting rumor list without Dwayne "The Rock" Johnson's name on it? The closest Johnson has come to play a superhero was the mythological figure Hercules in 2014.  Although the pre-production of DC's Black Adam has begun, we are referring only to Marvel. So, picturing him as Namor is simple and easy to understand.

Namor is Aquaman on steroids (look out Jason Momoa). He is a mutant who possesses super-strength and aquatic abilities who is trying to the right the wrong of the misjustices of the "land dwellers" (humans) committed against his home of Atlantis. Some marvel fans may know him as the Sub-Mariner.

Although still a rumor, it seems that he has been talking with Marvel executives about playing this character in an upcoming sequel to a popular Marvel movie – "Wakanda forever."

Jared Leto As Nightmare

Nightmare is a supervillain and the arch-nemesis of Doctor Strange, who may make his appearance in Doctor Strange in the Multiverse of Madness in 2021.

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The well-accomplished actor, scene-stealing Joker from Suicide Squad, Oscar winner Jared Leto is rumored to play the ruler of a Dream Dimension who can draw power from the minds of those who sleep. Very Freddy Kruegerish, but nevertheless creepy and fascinating. Leto has already played Joker in the previously mentioned Suicide Squad. Also, he will play the title character of Morbius later this year.

Tom Hardy As Wolverine

Yes, that's right, Tom Hardy, as Logan. The self-healing, Adamantium claw wearing, robust, uncompromising member of X-Men. Hardy as Wolverine would have been a marvel's fan dream. The role seems to fit him to a tee. We remember Tom Hardy as Baine in The Dark Night Rises when he famously stated, "You think darkness is your ally. You merely adopted the dark. I was born in it. Molded by it." MCU fans would have goosebumps thinking about the alternate universe of Hardy as Wolverine.

Matthew Vaughn, who produced X-Men: First Class, once stated that he saw Tom Hardy as a young Wolverine, but it was not to be.

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