The Marvel Cinematic Universe is nearly 10 years old and is comprised of over 40 current and future movies, television shows, digital series and movie shorts. This doesn’t even include the plethora of tie-in comics that Marvel publishes every year. We often focus all our attention on the superheroes who make up the Avengers and the Defenders. We may even remember some of the more notable villains these heroes have fought against. However, with all this content to peruse through, it can be easy to miss some of the characters that have appeared in Marvel’s overarching continuity.

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It should be no surprise by now that the MCU is loaded with hidden easter eggs that give the most devoted comic book fans something to smile about. Sometimes it can be the smallest reference, a quick cameo, or the shortest appearance, but many comic book characters have been caught by some of the most hawkeyed fans out there. Still, though, it’s hard to catch everything, and sometimes characters deviate so much from their comic book counterparts, that it’s difficult to catch each and every reference and name drop. Comic Book Resources has found 15 hidden characters who are secretly in the MCU. If you missed some of these, you’re excused.

15 HELLFIRE

The Inhumans arc in Agents of S.H.I.E.L.D. introduced many new superpowered beings into the world. It also introduced us to some hidden comic book characters, but JT James, aka Hellfire, was right in front of us the whole time. He was brought to Afterlife before getting himself kicked out. James later gains his Inhuman abilities and picks up his comic book moniker.

In the comics, James is a direct descendent of the Phantom Rider, and inherited the ability to control supernatural flames. He is recruited by Nick Fury as a member of the Secret Warriors and becomes a love interest to Daisy Johnson. It is eventually learned that he betrayed the team to HYDRA, and Fury kills him. They really took him in a different direction on the show, though.

14 NIGHTHAWK

The Marvel Cinematic Universe has made multiple references to the superhero Nighthawk at this point. The first time was in the Marvel One-Shot All Hail the King, when a man calling himself Jack Norriss entered Seagate Prison to kidnap Trevor Slattery. That name is used again in the May 3, 2016 episode of the WHIH Newsfront webseries. Norriss is the name of a S.H.I.E.L.D. agent turned reporter who briefly took on the Nighthawk mantle.

Kyle Richmond, the millionaire playboy who became the hero known as Nighthawk, was later name-checked in the first season of Daredevil. He was invited to Wilson Fisk’s gala but didn’t show up. Could this all be leading to an appearance of the character, or was this all just in the spirit of fun?

13 DOCTOR FAUSTUS

The first season of Agent Carter uses doctor Johann Fennhoff as the show’s main villain. He is a German scientist posing as a Russian doctor who wants revenge for what Howard Stark did during the war. As a gifted psychologist, Fennhoff has shown the ability to hypnotize people to get them to do what he wants.

Though his codename is never used, Fennhoff is actually the villain Doctor Faustus, a high-ranking official in HYDRA and a recurring enemy of Captain America. In the episode “Snafu,” he’s even seen reading Christopher Marlowe’s The Tragic Life of Doctor Faustus as a reference to his comic book counterpart. He was last seen in a prison cell next to Arnim Zola, and the two were seemingly plotting something bad.

12 THE ORIGINAL HUMAN TORCH

Before Johnny Storm took up the name the Human Torch as a member of the Fantastic Four, there was the android Jim Hammond. The original Human Torch was one of Marvel’s first superheroes. He fought alongside Captain America and Namor in the World War II-era group known as the Invaders.

Though Marvel has a vast supply of World War II superheroes, we don’t see much of that in Captain America: The First Avenger. What we do see, though, is the Synthetic Man on display at the 1943 Stark Expo, created by Doctor Phineas Horton. In the comics, Horton built the Human Torch, making it clear who the Synthetic Man is supposed to be. It’s too bad we never got to see the android in action though.

11 COLDBLOOD

Iron Man 3 villain Aldrich Killian had a personal enforcer named Eric Savin, as played by James Badge Dale. Savin is an ex-soldier who steals the Iron Patriot armor for A.I.M. in order to kidnap the President of the United States. He later gains incredible abilities from his exposure to the Extremis drug before he is killed by Iron Man.

Though the movie never refers to him by his codename, Eric Savin is the real name of the cyborg known as Coldblood. In the comics, Savin was a member of the US Army before he was betrayed and killed. When he was reborn as a cyborg, he gained superhuman abilities, some of which mirror his powers in the film when he was under the influence of Extremis.

10 CARINA TIVAN

When Volstagg and Sif took the Reality Gem to the Collector for safe keeping in the post-credits scene from Thor: The Dark World, a pink-skinned servant girl presented them to her master. It took until Guardians of the Galaxy to find out her name, but it was eventually revealed that this was Carina Tivan, the daughter of the Collector.

In the comics, Carina is sent by her father to seduce his enemy Michael Korvac, which eventually leads to their confrontation with the Avengers in “The Korvac Saga.” In GotG, she betrays the Collector and attempts to use the Power Stone against him, but it backfires and kills her instead. If Carina is really gone, maybe we won’t end up seeing Korvac in the Marvel Cinematic Universe.

9 BLACKWING

Joseph Manfredi, the criminal known as Blackwing, has a history of involvement with several supervillain criminal organizations. His father Silvermane is a leader in the international crime syndicate known as the Maggia. He has also been a member of the Circus of Crime, Masters of Evil, the Red Skull’s Skeleton Crew and HYDRA.

It should then be no surprise that Manfredi appeared in Season 2 of Agent Carter as a crime boss working within the Maggia. It’s certainly several decades earlier than his comic book equivalent would appear, but it’s clear that the Manfredi family is in control of the organization even back then. Manfredi appears in several episodes where he is seen working alongside Whitney Frost, the TV equivalent of the comic book villain Madame Masque.

8 MANIFOLD

It is mentioned in the Season 3 episode of Agents of S.H.I.E.L.D., “The Inside Man,” that the Australian government has taken an Inhuman named Eden Fesi into custody. In the comics, Fesi is the Mutant hero Manifold, who has the ability to teleport. He was held in custody by the military so they could examine his abilities and experiment on him.

S.H.I.E.L.D. was alerted to his existence and seized his documentation in order to discover his location. With this information, Phil Coulson was able to stage a rescue mission to get the Inhuman out of containment. Fesi’s test subject number read as SW4-7-2009, which is a direct reference to his first appearance in the comics—Secret Warriors #4 in July 2009.

7 UNION JACK

Captain America: The First Avenger didn’t just introduce us to Steve Rogers, Bucky and Peggy Carter, we also got a glimpse of the Howling Commandos in action. Among their members in the film was James Montgomery Falsworth, who shares a name with the British superhero Union Jack. He survived the events of the film, but when Captain America woke up in the 21st Century, Falsworth is listed as deceased.

It’s never made clear whether he went on to take his comic book alter ego, but if he did, it’s likely that his legacy lives on in the modern MCU. In the comics, Falsworth’s children followed in his footsteps as superheroes. He specifically passed on the mantle to his son Brian after his death. Joseph Chapman later took on the name in present day.

6 WHIPLASH

In Iron Man 2, Mickey Rourke’s Ivan Vanko character is a combination of Iron Man villains Whiplash and Crimson Dynamo. The actual Whiplash was later used on Agents of S.H.I.E.L.D., but in order to avoid confusion, his codename is never mentioned and his trademark whips are never seen.

In the episode “A Fractured House,” the character Marcus Scarlotti is an undercover HYDRA operative who is working within S.H.I.E.L.D. to undermine the organization. Mark Scarlotti is the civilian name of Iron Man villain Whiplash. Scarlotti wields a rope dart knife in his fight with Melinda May as a direct reference to his comic book identity. In the end, May used the weapon against its user in order to defeat him.

5 KID COLT

The MCU establishes Marvel’s Old West continuity from the comics in an episode of Agent Carter. In “Better Angels,” Howard Stark forms the film studio Stark Pictures in order to make a movie about the cowboy Kid Colt. He uses the in-universe comic book about the character as his reference.

Peggy questions his decision to make a film based on a comic (who could be so stupid!?), and he tells her that the comic was based on the real life Western hero. Kid Colt was one of Marvel’s longest running Western characters. If he has been confirmed as existing in the MCU, it’s interesting to wonder who else might have been out there with him. We need a time travel story in Agents of S.H.I.E.L.D. to find out.

4 THE LIVING TRIBUNAL

In the comics, the Living Tribunal is the arbiter of cosmic justice, and is essentially the most powerful entity in the Marvel Multiverse just beneath the One Above All. For someone so important and powerful, you would expect to see him show up in Guardians of the Galaxy or make a grand entrance in Avengers: Infinity Wars. Instead, his name gets quietly dropped in Doctor Strange.

In the 2016 film, Karl Mordo wields a weapon called the Staff of the Living Tribunal. It’s the staff he uses to train Doctor Strange, and it can take different forms to serve as several kinds of weapons. The Living Tribunal is so powerful that he doesn’t need a weapon, but if his name is showing up in the MCU, it can’t be long before we see him in "person."

3 STARHAWK

Guardians of the Galaxy Vol. 2 introduced a very unexpected group of characters in the Guardians 3000. Chief among the them were Stakar Ogord and Aleta, who were played by Sylvester Stallone and Michelle Yeoh. In the film, they are members of the Ravagers and old friends of Yondu. In the comics, these two were merged by the power of the Hawk God into the entity known as Starhawk.

Referred to as the One-Who-Knows, Starhawk owns an incredible amount of godlike power. He also has the ability to alter and shape the future because he has existed in countless alternate universes. Stakar and Aleta didn’t become an all-powerful cosmic entity in the movie, but we don’t know what James Gunn has in store for Guardians of the Galaxy Vol. 3.

2 MANDARIN

Ben Kingsley Iron Man 3 Mandarin

Marvel had hinted at the existence of the Mandarin since Iron Man first saw theaters in 2008. The Ten Rings terrorist organization is a direct reference to the character’s mystical rings. Jon Favreau even had plans to introduce him in Iron Man 3 before he left the franchise. When the character finally showed up, it turned out that Ben Kingsley was actually playing an English actor who was playing the Mandarin.

Fans hated the reveal so much that Marvel actually set out to fix their mistake. All Hail the King was released on the home media release for Thor: The Dark World in 2014. The 14-minute Marvel One-Shot confirmed that the Mandarin was actually real when he sent an agent to capture Trevor Slattery and force him to answer for his crimes.

1 MAN-THING

Believe it or not, the Marvel Cinematic Universe contains multiple references to the existence of Man-Thing. In Iron Man 3, Tony Stark fights Ellen Brandt, an agent of A.I.M. who has been infected with the Extremis virus. In the comics, Brandt is the wife of Man-Thing, aka Ted Sallis. The scar on her face is said to be a reference to his acid attack on her.

Man-Thing is directly name dropped by Maria Hill in the Agents of S.H.I.E.L.D. Season 1 episode “Nothing Personal.” She is seen leaving a Congressional hearing while discussing those who are under S.H.I.E.L.D. surveillance on a phone call with Pepper Potts. It was also recently discovered that Man-Thing’s face is visible on the Grandmaster’s palace in Thor: Ragnarok.

Which other secret Marvels have you noticed in the MCU? Help us complete out list in the comments!