Even in a franchise as big as the Marvel Cinematic Universe, there's no way every character can be given the attention they need or deserve. The trio that made up the Warriors Three are perfect examples of heroes who never quite got their due, but at least their story was given an ending (albeit an unsatisfying one).
They should count themselves lucky, though, because there are some characters who were totally overlooked after their first appearances; in fact, we'd go so far as to say they were forgotten.
These heroes, villains, and supporting players all had heaps of potential in the MCU. That might explain why one or two are now returning, but we'd still like to know what happened to them in the first place...and what led to Marvel Studios deciding to move on with such little fanfare.
To take a look at these poor forgotten heroes and villains, simply click the "Next" button below!
8. Nova Prime
Convincing Glenn Close to join the MCU was a big win for filmmaker James Gunn as he developed Guardians of the Galaxy for Marvel Studios.
Her role as Nova Prime was minor, but still crucial to how the story played out. Richard Rider was M.I.A., but the existence of the Nova Corps proved to be more than enough to leave fans chomping at the bit for their MCU future.
Unfortunately, Thanos decimated them off camera in Avengers: Infinity War, so we can only assume Nova Prime was among the fallen, because Marvel Studios has never bothered to address what became of the interplanetary police force.
Did Thanos leave half of them alive? Are they all dead? Who knows.
7. Aaron Davis
Atlanta star Donald Glover is one of the biggest talents working today, and even those who hated Solo: A Star Wars Story agreed that his take on Lando Calrissian was a highlight.
Bringing the actor into the MCU was huge, but as Aaron Davis (Miles Morales' uncle, and the vigilante known as Prowler), he brought little to the table in Spider-Man: Homecoming. A funny exchange with the inexperienced wall-crawler followed, as did a throwaway mention of Aaron's nephew.
What felt like a perfect way to introduce Prowler and/or Miles in the sequel was completely overlooked, which is no great surprise when Peter Parker was heading overseas. Unfortunately, Spider-Man: No Way Home also failed to bring Aaron back, so we can only hope he gets his due down the line.
For now, what a waste.
6. Betty Ross
Betty Ross is the definitive Bruce Banner love interest, and Liv Tyler did nothing but good work in 2008's The Incredible Hulk.
When that film was released, the plan at Marvel Studios was to have Earth's heroes assemble to fight a Hulk who had fallen under the control of Loki. When Joss Whedon boarded the project, the idea was overhauled, and the Green Goliath's story played out in an entirely different way.
It's likely Betty was once part of The Avengers, but Bruce moved on to Black Widow, and then left the planet entirely. He's back now, though, and has Bruce's intelligence.
Despite all of that, it seems he's never once looked Betty up. Marvel, meanwhile, has forgotten all about the bond these two share. Perhaps she'll get a mention in She-Hulk?
5. Dr. Selvig
In the early days of the MCU, Dr. Erik Selvig was a major part of how the stories in this shared world unfolded. He was in Thor, then The Avengers. He was crucial to Thor: The Dark World, too, and even showed up Avengers: Age of Ultron.
Avengers: Endgame confirmed he was among those Thanos snapped out of existence, but that means he eventually came back with everyone else. Only Spider-Man: Far From Home has covered the aftermath of the Blip, so Selvig could return, but as it stands, he's still been M.I.A. for going on six years.
When and why did he stop being so important to the MCU?
When Joss Whedon left by the looks of it, and Marvel Studios instead decided that these heroes didn't need the assistance of a big brain like Selvig.
4. Mitchell Carson
Once a major player in S.H.I.E.L.D., it was later revealed that Mitchell Carson was another undercover HYDRA operative. That was why we saw him in Ant-Man attempting to acquire the Yellowjacket armor.
That plan failed, but he made it out of Darren Cross' building alive to fight another day.
He wasn't completely empty-handed, however, as his briefcase was full of Pym Particles. There's a lot that could be done with those vials, but there's been no sign in the past six years that Marvel Studios plans to either bring Carson back or reveal what ended up happening to them.
Marvel forgot this character, while creating what some might describe as a plot hole.
3. Dr. Cho
With the Chinese box office becoming increasingly important, many film studios in the mid-2010s realising that embracing the Middle Kingdom might increase the chances of success in the country.
Iron Man 3 included scenes specifically shot for China, though many filmgoers there took umbrage with the way they were presented. Despite that, Avengers: Age of Ultron still prominently featured Claudia Kim, an actress who is a big star in that part of the world.
As Dr. Helen Cho, she played a crucial role in how the sequel panned out.
Despite being attacked by Ultron, Cho later joined the staff of the New Avengers Facility...and hasn't been seen since.
2. Rhomann Dey
It's all too easy to forget just how impressive Guardians of the Galaxy's cast was, with John C. Reilly another big name we never expected to see in the MCU.
As Rhomann Dey, he made a lasting impact, and added even more heart to a film packed full of it.
Like Nova Prime, he's been missing in action since 2014; having him cross paths with the team again in Vol. 2 would have been easy enough. Unfortunately, we're again left to assume that both her, and his family, were victims of Thanos when the Mad Titan attacked Xandar.
We hope there's a future for him in Vol. 3, but only if Marvel remembers him.
1. Dr. Leonard Samson
Ty Burrell became a huge star after starring in The Incredible Hulk thanks to Modern Family, but Marvel Studios still failed to bring the actor back to the MCU as Dr. Leonard Samson.
That's a weird decision, and this psychiatrist could have fitted into any number of films. For starters, he could have been the shrink Tony Stark spoke to at the end of Iron Man 3; albeit transformed into his heroic alter ego as Doc Samson. That would have required more screentime, though, and more than just the cameo he made in 2008.
It seems Marvel never had any serious plans for Samson, with his inclusion being little more than an Easter Egg for fans.
It's no wonder, then, that he ended up being forgotten, but we'd love to see him get a second chance in She-Hulk this year.