The Avengers: Earth's Mightiest Heroes!

The Avengers: Earth's Mightiest Heroes aired in October 20, 2010, and ended in March 24, 2013.

Season 1:
As the world's most dangerous super-villains break out of the Vault, the Cube, the Big House, and the Raft, five of Earth's mightiest heroes assemble a crime fighting alliance called the Avengers. The Avengers team includes Iron Man as team leader, Ant-Man, Thor, The Hulk, and The Wasp. Captain America, Black Panther, and Hawkeye have since joined the roster. When it comes to the Season Finale, it was revealed that Thor's brother Loki was responsible for the breakouts and having Enchantress form the Masters of Evil.

Season 2:
Season Two will depict the Avengers as they track down the remaining members of the Masters of Evil and end up getting involved in the upcoming war between the Kree and the Skrull. The Avengers are unaware that Captain America has been replaced by a Skrull. Ms. Marvel, Vision, Falcon, and Mockingbird will join the Avengers. Many other characters from the Marvel Universe such as Doctor Doom, Surtur, Thunderbolt Ross' Red Hulk form, and Guardians of the Galaxy have been confirmed to make appearances. Series producers Joshua Fine and Christopher Yost have revealed that certain returning characters will adapt their Ultimate Universe counterpart costumes, such as Director Fury who returns in Season 2 appearing more like the Ultimate Universe Fury with a shaved head and goatee and the Skrull who replaced Captain America will wear the costume directly adapted from Ultimate Captain America and will use an energy shield.

Season 3:
???

The Avengers:

 * Iron Man (Eric Loomis) - leader, later gaves the leadership to Captain America and formed the Illuminati with Black Panther
 * Ant-Man (Wally Wingert) -
 * Thor (Rick D. Wasserman) -
 * The Hulk (Fred Tatasciore, Gabriel Mann) -
 * Wasp (Colleen O'Shaughnessey) -
 * Captain America (Brian Bloom) - the new leader
 * Black Panther (James C. Mathis III) - left with Iron Man to form the Illuminati
 * Hawkeye (Chris Cox) - quits the Avengers in "Obsessions of Doom" and forms the West Coast Avengers as the leader
 * Ms. Marvel (Jennifer Hale) -
 * Vision (Peter Jessop) -
 * Spider-Man (Drake Bell) - becomes a reservist in "New Avengers"

Allies:

 * The Private War of Doom:
 * Fantastic 4:
 * Mr. Fantastic (Dee Bradley Baker) -
 * Invisible Woman (Erin Torpey) - replaced by a Skrull
 * Human Torch (David Kaufman) -
 * Thing (Clancy Brown) - The Fred Tatasciore one was actually a Skrull!
 * Alone Against A.I.M.:
 * War Machine (Bumper Robinson) -
 * Pepper Potts (Dawn Oliveri) -
 * Acts of Vengeance:
 * Balder (Nolan North)
 * Welcome to the Kree Empire:
 * Captain Mar-Vell (Roger Craig Smith) -
 * Abigail Brand (Mary Elizabeth McGlynn) -
 * Sydren (Troy Baker)
 * Henry Gyrich (Jim Ward)
 * To Steal an Ant-Man:
 * Luke Cage (Christopher B. Duncan) -
 * Iron Fist (Loren Lester) -
 * Scott Lang/Ant-Man (Crispin Freeman)
 * Cassandra Lang (Colleen O'Shaughnessey)
 * Michael Korvac:
 * Guardians of the Galaxy:
 * Star-Lord (Steve Downes)
 * Adam Warlock (Kirk Thornton)
 * Groot (Troy Baker)
 * Rocket Raccoon (Greg Ellis)
 * Quasar (Moira Quirk)
 * Carina Korvac (Jennifer Hale)
 * Who Do You Trust?:
 * Quake (Lacey Chabert)
 * Black Widow (Vanessa Marshall) - revealed to have lied to Iron Man, and the Avengers to get them off her back!
 * The Ballad of Beta Ray Bill:
 * Beta Ray Bill (Steven Blum)
 * Lady Sif (Nika Futterman)
 * Behold...The Vision:
 * Jane Foster (Kari Wahlgren)
 * Winter Soldier:
 * Winter Soldier
 * Obsessions of Doom:
 * West Coast Avengers:
 * Hawkeye (Chris Cox) - leader
 * Mockingbird (Elizabeth Daily)
 * War Machine (Bumper Robinson)
 * Tigra (Claudia Black)
 * Wonder Man (Phil LaMaar)
 * Thing (Clancy Brown)
 * U.S. Agent (Patrick Warbutton)
 * War of the Worlds:
 * Illuminati:
 * Iron Man (Eric Loomis)
 * Black Panther (James C. Mathis III)
 * Mr. Fantastic (Dee Bradley Baker)
 * Blackbolt (Robert Patrick)
 * Professor Xavier (Jim Ward)
 * Doctor Strange (Xander Berkley)
 * Namor (James Patrick Stewart)
 * Inhumans:
 * Medusa (???)
 * Karnak (???)
 * Gorgon (???)
 * Triton (???)
 * Crystal (???)
 * Maximus the Mad (???)
 * Lockjaw (???)

Season 1:

 * Loki (Graham McTavish) - One of the key villains of Season 1
 * Baron Strucker (Jim Ward) - One of the key villains of Season 1
 * Ultron (Tom Kane) - One of the key villains of Season 1
 * M.O.D.O.C. (Wally Wingert) - One of the key villains of Season 1
 * Kang the Conqueror (Jonathan Adams) - One of the key villains of Season 1
 * Leader (Jeffrey Combs) - One of the key villains of Season 1
 * The Masters of Evil:
 * Baron Zemo (Robin Atkin Downes)
 * Enchantress (Kari Wahlgren)
 * Executioner (John DiMaggio)
 * Crimson Dynamo (Chris Cox)
 * Abombination (Robin Atkin Downes)
 * Wonder Man (Phil Lamaar)
 * Chemistro (Nolan North)
 * Living Laser (Nolan North)
 * Grey Gargoyle (Troy Baker)
 * Arnim Zola (Grant Moninger)

Season 2:

 * Kang the Conqueror (Jonathan Adams - fake voice, Jonathan Freeman - real voice) - the main antagonist, revealed to have caused the Kree and Skrull war to blame Captain America, and with him out of the way, he will complete his conquest as if it has never stopped!, finally defeated in War of the Worlds and was sent back to the Cretaceous as punnishment for his lies, and alterating time, the dinosaur he was chased by was a Carnotaurus!
 * Red Skull (Steve Blum) - revealed to be alive and the one reason why Fury is after Hydra, disguised as the President of the United States to put the blame of Skrull Invasion on Captain America, defeated and was locked up in Prison 41!, ???
 * A.I.M.:
 * Scientist Supreme (Nolan North)
 * Dr. Lyle Getz (Kyle Hebert)
 * Thaddeus Ross/Red Hulk (Keith Ferguson/Fred Tatasciore)
 * Lethal Legion:
 * Dr. Doom (Lex Lang) - the primary antagonist in Season 2, and was finally defeated in "Obsesstions of Doom"!, and stripped of His Diplomatic Immunity!
 * Kurse (Clancy Brown) - posed as Odin in Season One, and 2 and released Surtur!
 * Grim Reaper (Lance Henrikson) - ???
 * Man Ape (Kevin Michael Richardson)
 * Moonstone (Jennifer Hale)
 * Awesome Man (Jenson Ackles)
 * Swordsman (Rene Auberjoinis)
 * Surtur (Rick D. Wasserman) - revealed to be freed by the Fake Odin to Keep Thor in Asgard to keep him in Power, reimprisoned with the help of Thunderstrike and Beta Ray Bill!
 * The Masters of Evil II:
 * Ultron-7/Crimson Cowl (Tom Kane) - the leader
 * Klaw (Mark Hamill)
 * Whirlwind (Troy Baker)
 * Melter (Eric Bauza)
 * Radioactive Man (James Sie)
 * Black Knight (J.B. Blanc) - revealed to be an agent under Nick Fury's orders
 * Dark Avengers:
 * Norman Osborn/Iron Patriot (Mark Rolston) - the leader, ???
 * Mac Gargan/Venom/"Spider-Man" (Tim Curry)
 * Karla Sofen/Moonstone/"Ms. Marvel" (Tara Strong)
 * Lester/Bullseye/"Hawkeye" (Steven Blum)
 * Daken Akihiro/"Wolverine" (James Sie)
 * Noh-Varr/Captain Marvel (Jim Meskimen)
 * Ares (Troy Baker)
 * Robert Reynolds/Sentry (Nolan North)
 * Skrulls:
 * Super Skrull (Kyle Hebert) - Leader of the fleet of Skrull's, and the one who listened to Kang's details of Conquest!
 * Veranke (Elizabeth Daily)
 * Kree:
 * Kalum Lo (Fred Tatasciore)
 * Ronan the Accuser (Keith Szarabajka)
 * Sentry-459
 * Supreme Intelligence (David Kaye)
 * Yon-Rogg (Fred Tatasciore)

Season 3:

 * Thanos (Michael Ironside) - the main antagonist

Other villains

 * Absorbing Man (Rick D. Wasserman)
 * Annihilus - ???
 * Armadillo
 * Bi-Beast
 * Blizzard (Troy Baker) - killed by the Annihilation Wave in "Assault on 42"
 * Crossfire (Neil Ross)
 * Galactus
 * Glenn Talbot (Troy Baker)
 * Graviton (Fred Tatasciore)
 * Griffin (Fred Tatasciore)
 * Heralds of Galactus
 * Air-Walker
 * Firelord
 * Stardust
 * Terrax (Kevin Grevioux)
 * Michael Korvac (Troy Baker)
 * Lucia Von Bardas (Kirsten Potter)
 * Mad Thinker (Danny Mann)
 * Malekith (Quinton Flynn)
 * Mandrill (Fred Tatasciore)
 * Purple Man (Brent Spiner)
 * Professor Thornton (Tom Kane)
 * Ravonna (Cindy Robinson)
 * Red Ghost
 * Serpent Society:
 * King Cobra (James C. Mathis III)
 * Anaconda (Vanessa Marshall)
 * Bushmaster
 * Constrictor (Cam Clarke in Season 1, Troy Baker in Season 2)
 * Death Adder
 * Rattler (Chris Cox)
 * Madame Viper (Vanessa Marshall)
 * Sinister Six:
 * Norman Osborn/Green Goblin (Mark Rolston for Norman Osborn and Iron Patriot, Kevin Michael Richardson for Green Goblin)
 * Dr. Octopus (Corey Burton)
 * Venom (Travis J. Gould)
 * Sandman (Wade Williams)
 * Rhino (???)
 * Scorpion (???)
 * Technovore (Dwight Schultz)
 * U-Foes:
 * Vector (Cam Clarke)
 * Ironclad
 * Vapor (Colleen O'Shaughnessey)
 * X-Ray
 * Ultimo
 * Whiplash
 * Wrecking Crew:
 * Wrecker (J.B. Blanc)
 * Bulldozer (James C. Mathis III)
 * Piledriver (Nolan North)
 * Thunderball (Gary Anthony Williams)
 * Zzzax