A group of high-tech mercenaries.

A group of villains given powers by extradimensional beings as part of a contest to see which was most powerful. The most famous of the Exemplars is none other than the Juggernaut.

Forced to leave their homeland, Growler, Howler, and Gorr explore the world in search of the Tana Moon for their friend Superboy.

A group infected with the Theta-virus brought together by Dr. Rachel Deming to help cure and train them as they developed into Ultras. Based on Stronghold, an island off the coast of California.

The Exiles are group of time and space traveling characters that are charged with the duty of jumping across multiple parallel realities. In each reality they must resolve a certain issue before they can move on to the next one in order to save the Multiverse.

The second team with this name, the Exiles are a renegade group brought together by the events of Black September and includes characters from the Marvel Universe.

A group of international would be world conquerers that were allies of the Red Skull who fought against such heroes as Captain America and his side-kick the Falcon, and later Dr. Doom. Their base of operations is the appropriately named Isle of Exiles.

In the post apocalyptic future of the Earth which was decimated by a planet scale nuclear war, the hapless survivors and their offspring have been horribly mutated by the toxins released into the environment. The Ex-Mutants are a group of former mutants who were returned to their humanity by Dr. Emmanuel Cugat. They were created and than trained in the arts of battle to return Earth to hopeful future.

A rebooted version of the original Ex-mutants (1987) with new characters and setting.

One of the Builder races, the Ex Nihili are gardeners, charged with seeding a world with new life after an Aleph has razed it to the ground.

Humans trained and armed with neural network helmets to control the animal population on the terraformed planet, Exodus

The Experimentals are a team of superheroes that reside in Astro City.

Explorer-Class Adaptoids are a enhanced model of Adaptoid created by A.I.M. with the purpose of mining the multiverse.

Three energy-consuming monsters that were locked away in the space between dimensions by the Celestials.

Robots created by Dracus to exterminate renegade androids.

Team assembled by Chameleon to attack Peter Parker.

All members of the Externals were shown to be immortal and important to Apocalypse's rise of power, now only three of them remain...though even those seem to have lost all connection to one another.

The Extreme Emergency Team is part of the New York Police Department. The team was created for emergencies.

Extreme Justice was formed by Captain Atom as a pro-active attack on the darker forces rather than a reactionary defense.

The Extremists are an outlaw group of villains from Earth-8. And the destroyers of their own world in a previous continuum.

A demonic race used by Doctor Strange to enforce security on "Strangetown".

The Fables are those of the childhood stories. After being forced to flee their homelands, they currently reside in the fictional land of New York.

These are the creatures that come from eggs, laid by the Alien Queen, and put Alien embryos in humans, animals, and Predators. Like the Aliens, their blood is also acidic.

The Faceless Ones or Those Who Dwell Below are a primitive underwater green-skinned race with pointed ears, webbed hands and feet, vestigial wings, and no facial features that are savage and carnivorous.

The Federal Advisory Committee to Thunderbolts was a corrupt government organization that used the prisoners at the Raft as superhuman weapons. Luke Cage and his Thunderbolts discovered their designs and dismantled the organization.

A news station.

The Factor are an elite unit of the Imperial High Guard of D'Vor. The are enemies of both Brigade and The Birds of Prey.

Adversarial group of the X-Men.

A fairy is a mythological creature foremost from European folklore.

Super-villains claiming to be the Defenders to perpetrate crimes

A group from the 31st century and enemies of the legion of superheroes. They used the green lantern myth to drive fear into there victims.

One of the most infamous criminal organizations in Gotham City, headed by patriarch Carmine "The Roman" Falcone.

Hollow-boned performers at the Interstellar Circus Spectacular.

An alien race from the Star Wars Universe, Falleen can change their skin pigment and emit pheromones that make them irresistible to many other races. They're somewhat of a reptilian/mammalian hybrid referred to as reptomammalian. Many Falleen have been seen as heavily tied to the Black Sun crime syndicate.

Originally a group of pick-pockets and thieves, the Fallen Angels later consisted of runaway young mutants and cyborgs who had an intergalactic adventure. Recently, Revanche (now renamed Psylocke) formed a new team along with X-23 and the time-displaced Cable.

The Fall people are allies of the X-Men in the Savage Land. A member of the tribe, Nereel, is the mother of Peter Rasputin's alleged son, Peter.

Falsebloods are the offspring of a Highborn and a human.

Though the concept was originally invented by the Joker, the False Face Society is best known today as the name of Black Mask's criminal organization. Both stressed the same theme: masks on the faces of all members.

Extradimensional powerful energy beings of whom Dormammu originates.

The defenders of Storm City, who use their mystical Elemental Rings to battle the forces of evil.

The Fraternity of Atavistic No-goodniks is an evil super team of atavistic evolutionary throwbacks. .

Fanatix is an extremist mutant group that want nothing to do with humans. Fanatix consist of deadly mutant mercenaries that come into conflict with Bishop and XSE, the Xavier Security Enforcers.

Criminal gang in Harlem.