Earth's Mightiest Heroes are the stuff of legend. Yet the team was not always the playground for the who's who of metahumans that it is now. In fact, before the Marvel Cinematic Universe emerged, very few top tier heroes were on the Avengers team at all.

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At points in its membership, it did not even have Iron Man, Captain America, and Thor in its ranks. Instead, heroes like the Black Knight, Sersi, and Crystal made up the bulk of the squad. For every Captain America that has to lead the team, there has been a Doctor Druid. For every absent Hulk, there have been bit-part appearances from the Thing. Unfortunately, not all Avengers go down in history.

10 Gilgamesh The Forgotten One

Gilgamesh forgotten one

Gilgamesh, also known as the Forgotten One, is one of the more well-known of The Eternals. Created by Jack Kirby, they are a near-immortal, hidden galactic race who had existed since the beginning of time. Unfortunately, the Forgotten One was cast out for his fascination with mortal affairs. Taking the name Gilgamesh, he roamed the earth assisting humans in their quests for justice.

When the Avengers roster was depleted, Gilgamesh joined up with them. He assisted the team until he was killed in battle with Kang. Unbeknownst to his teammates, he had actually been reborn. The most touching story of this character's rebirth was one in which he shared a flat with the Avenger Hercules. The two gods would work together on the very mortal problem of overcoming a period of poor mental health.

9 Captain Britain (Lionheart)

Captain Britain Lionheart

Many fans know Captain Britain as Brian Braddock. However, the first Captain Britain to be an Avenger was a female version of the character. Kelsey Leigh was a single mother who died protecting her children from the Wrecking Crew using Captain America's shield.

Granted honorary status, she became one of only two people to become an Avenger in their civilian guise (Hank Pym is the other). Unbeknownst to the Avengers, she had actually been reborn as the new Captain Britain, chosen by the deceased Braddock himself. When he returned to the mortal world, she would keep her powers but have her name changed to Lionheart.

8 Sandman's Shift Between Good & Evil

sandman avenger

While many fans know the Sandman as one of the Spiderman rogues galleries, not many realize he was actually an Avenger. In fact, it was the Fantastic Four's Thing who made him question his bad choices and turn over a new leaf. He would then assist Spiderman, Silver Sable, and other reformed villains in the fight against crime.

After a presidential pardon for past misdemeanors, he became a reserve member of the Avengers. The path of the hero did not last long. After an outcry from fans who had enjoyed his stint as a hero, Marvel had to push out a messy retcon in which he had been controlled by the Wizard. After this, he would flirt the boundary of good and evil, dependent upon who was writing the character.

7 Sersi & Her Erratic Behavior

Sersi from Marvel's Eternals

Like the Forgotten One, Sersi is a member of the race known as the Eternals. Before her stint in the Avengers, she adventured throughout history before becoming a wealthy socialite in New York. At one of her famous parties, she invited the Avengers and found herself besotted with Captain America.

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When her fellow Eternal, Gilgamesh, was seemingly killed, Sersi was invited to take his place in the team. Her time with the Avengers was turbulent, with her behavior becoming increasingly erratic and violent before her departure. Sersi was recently believed to have died when the race of Eternals was driven mad.

6 Silverclaw Despite Her Heartwarming Backstory

Silverclaw

Of all the minor Avengers, Silverclaw has the most heartwarming backstory. A child born of a human father and a volcano goddess in a small Costa Verde village, she was placed into an orphanage upon the death of her father. When the Avengers Butler Edwin Jarvis set up a charitable sponsor program from his own salary, she was matched to him due to her emerging powers.

She would write to her sponsor regularly, and when she came to the U.S. to study made contact with her benefactor. This eventually leads her into contact with the Avengers, with whom she became an occasional member.

5 Doctor Druid The Psychologist

Doctor Druid from Marvel Comics

A trained psychologist who studied at Harvard, Anthony Ludgate also had a passion for the occult. He studied the ancient religion of his homeland, England, and followed a path of paganism and the ways of the druid. In his 60s appearances, he was known as Doctor Droom but later vanished into comic obscurity. It was not until the 70s when he resurfaced as Doctor Druid.

After stints in Ghost Rider and the Incredible Hulk, Doctor Druid would join the Avengers. Mind-controlled by the villain Terminatrix, he would spend his tenure trying to turn the team on itself, even becoming the leader at one stage. When freed, he would fake his own death due to the shame his actions brought upon him.

4 Living Lightning As A Member Of Other Teams

Living Lightning Being Shot At While He Sends Out Bolts Of Electricity

Miguel Santo's father, Carlos, was a member of the Legion of Living Lightning. When he died in battle, Miguel broke into their headquarters. He was inadvertently turned into a being of pure electricity. After a short criminal career, he would meet the West Coast Avengers and begin a new life as a member.

Miguel would join a number of teams after this, including the Rangers, a team of heroes formed to defend Texas. He once turned down an offer to join the Great Lakes Avengers. Originally signing up, he had believed their acronym stood for the Gay and Lesbian Alliance.

3 Two-Gun Kid Who Traveled Through Time

Two Gun Kid

The Two-Gun Kid has a long history in Marvel Comics. Originally, he was a character in their Western Imprints when the company was known as Timely. In the silver age, a new version of the character helped the Avengers fight Kang the conqueror in 1870. He would strike up a friendship with Hawkeye, who would be his chaperone as he explored the future in reserve Avenger status.

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Two-Gun Kid would bounce backward and forward in time for many adventures after this. The fan-favorite She-Hulk run from Dan Slott reimagined him as a bounty hunter. He would work with Jennifer Walter's law firm to apprehend criminals while sharing a room with a reformed version of the Awesome Android.

2 Firebird The Social Worker

Firebird

Before becoming a member of the Avengers West Coast, Bonita Juarez was a founder member of the Rangers. This team was a group of heroes scattered across the South West of the U.S, who would later become a unit of the 50 States Initiative.

A true hero, she chooses to locate herself in her home region of New Mexico. Here, she divides her time between being a superhero and a social worker. Her caring nature was cemented when she first joined the Avengers. On her first day, she prevented Hank Pym from committing suicide in the absence of his teammates.

1 Triathlon & His Enhanced Spiritual Enlightenment

Triathlon

Stripped of his three gold medals due to steroid abuse, Delroy Garret turned to religion. His first stop was the cult-like Triune Understanding, who used his celebrity status to position him as a spokesperson. Unbeknownst to Delroy, he was given powers from a mysterious object. However, he believed they had come from his enhanced spiritual enlightenment.

Eventually, he came into contact with the Avengers and was pushed to gain membership by his benefactors. His membership was short and characterized by the outing of the Triune Understanding as a front for an alien invasion. He would later change his name to the 3-D Man upon leaving the team.

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