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 The Avengers are unaware that Captain America has been replaced by a Skrull.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 have gained the West Coast Avengers, and must prove they can deal with Thanos! Due to Thanos murdering, the season will have a darker tone, Wasp grows her hair, and now wears a ponytail, similar to her character in The Avengers: United They Stand, and Ms. Marvel's costume now shows her bare midrift, and she has shorter hair and some episodes will focus on the current Avengers, while other episodes focus on West Coast Avengers.

The Avengers:

 * Captain America (Brian Bloom) - the new leader of the Avengers in season 3
 * Hulk (Gabriel Mann/Fred Tatasciore)
 * Hank Pym/Ant-Man/Yellowjacket (Wally Wingert) - became Yellowjacket in "Yellowjacket"
 * Thor (Rick D. Wasserman) -
 * Wasp (Colleen O'Shaughnessey) -
 * Ms. Marvel (Jennifer Hale) -
 * Falcon (Lance Reddick) -
 * Vision (Peter Jessop) -
 * Quicksilver (Mark Hildreth) - joined in season 3
 * Scarlet Witch (Kate Higgins) - joined in season 3

West Coast Avengers:

 * Hawkeye (Chris Cox) - the leader, revealed in "Obsessions of Doom" that he wants to add Mockingbird to the Avengers! He is awarded the agent of the year by Fury!
 * Mockingbird (Elizabeth Daily)
 * Tigra (Claudia Black) - Starts out as a mysterious creature that science, nor magic could solve!
 * War Machine (Bumper Robinson)
 * Wonder Man (Phil LaMarr)
 * Thing (Clancy Brown in season 3) - only for a short time
 * Marc Spector/Moon Knight (Jenson Ackles)
 * Bonita Juarez/Firebird/La Espirita (Maria Canals) - she joined after preventing Hank Pym from dying to Ultron

Inhumans:

 * Medusa (Grey DeLisle)
 * Karnak (Steven Blum)
 * Gorgon (Greg Eagles)
 * Triton (Richard Green)
 * Crystal (Kim Mai Guest)
 * Maximus the Mad (Troy Baker)
 * Lockjaw (Dee Bradley Baker)
 * Sentry 219 (Mark Hamill)

Fantastic Four:

 * Mr. Fantastic (Dee Bradley Baker)
 * Invisible Woman (Erin Torpey)
 * Human Torch (David Kaufman)
 * Thing (Clancy Brown)

X-Men:

 * Cyclops (Nolan North)
 * Jean Grey (Jennifer Hale)
 * Wolverine (Steve Blum)
 * Colossus (Phil Morris)
 * Storm (Susan Dalian)
 * Thunderbird (Michael Horse)
 * Banshee (Nick Chunlind)
 * Kitty Pryde (Tara Strong)

The 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)

S.H.I.E.L.D.:

 * Nick Fury (Alex Desert)
 * Black Widow (Vanessa Marshall) - revealed to have lied to Iron Man, and the Avengers to get them off her back!, She was secretly working for Kang to help Russia return to its glory! As a punishment, Hawkeye knocks her out, and returns her to Russia to answer for her crimes!
 * Yelena Belova/Black Widow II (Kath Soucie) - the new Black Widow after Natasha was sent to Russia to answer for her crimes
 * Quake (Lacey Chalbert)
 * Maria Hill (Kari Wuhrer)
 * Clay Quartermain (Troy Baker)
 * Jimmy Woo (Nolan North)
 * Jasper Sitwell (Tom Kane)
 * Phil Coulson (Clark Gregg)

Allies:

 * Pepper Potts (Dawn Oliveri) -
 * Balder (Nolan North)
 * Captain Mar-Vell (Roger Craig Smith) -
 * Sword:
 * Abigail Brand (Mary Elizabeth McGlynn) - gets transferred to Stark Indaustries!
 * Sydren (Troy Baker)
 * Henry Gyrich (Jim Ward)
 * Luke Cage (Christopher B. Duncan) -
 * Iron Fist (Loren Lester) -
 * Scott Lang/Ant-Man (Crispin Freeman)
 * Cassandra Lang (Colleen O'Shaughnessey)
 * 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)
 * Beta Ray Bill (Steven Blum)
 * Lady Sif (Nika Futterman)
 * Jane Foster (Kari Wahlgren)
 * Winter Soldier (Jon Curry)
 * Tyrone "Ty" Johnson/Cloak (Khary Payton)
 * Doc Samson (Cam Clarke)
 * Odin (Corey Burton) - more like the like action version, and one eye to prove he is the real one since Kurse posed as him!
 * Silver Surfer (Yuri Lowenthal)

Season 1:

 * Loki (Graham McTavish) - the main antagonist, was the cause of the Breakouts, and had the Enchantress form the Masters of Evil
 * 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) - revealed to be the son of Baron Zemo, and realizes the true potential and heart of Captain America and asks for a truce!
 * 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 Freeman) - he is the main antagonist of season 2, he escapes to stop the Avengers once again before they end up causing the destruction of his timeline by letting Black Panther live during the destruction of Earth's Sun by the Kree, after he was defeated in "War of the Worlds", Kang later was banished into the Cretaceous being chased by a Carnotaurus stating "Curse you Avengers!"
 * Immortus (Arnold Vosloo) - He was partially responsible for the creation of the Vision, allegedly creating a temporal copy of the original Human Torch that the android Ultron used to create the Vision.
 * Rama-Tut (Jim Meskimen) - he met his ancestor, Dr. Doom
 * Scarlet Centurion (Jonathan Adams) - Thinking to use this version of Earth as his base, he manipulated the Avengers of that world - the original team - into capturing every other super powered being, whether hero or villain, on the planet. Once this was accomplished, he transported the Earth-616 (mainstream) Avengers to fight their -689 counterparts. Once one team was defeated, the Centurion planned to defeat the other himself and then rule the world unopposed. The -616 Avengers won the day and furthermore succeeded in driving Kang out of the time-stream.
 * Red Skull (Steve Blum) - revealed to be alive, disguised as Dell Rusk, the head of the US Dept. of Security, to finally have his revenge on Captain America, defeated and was locked up in Prison 42.
 * Thaddeus Ross/Red Hulk (Keith Ferguson/Fred Tatasciore) - Ross is transformed into the Red Hulk by the Winter Soldier on orders from Red Hulk in order to finally have his revenge on Hulk.
 * A.I.M.:
 * Scientist Supreme (Nolan North)
 * Dr. Lyle Getz (Kyle Hebert)
 * Lethal Legion:
 * Dr. Doom (Lex Lang season 2, Mark Hamill season 3) - One of the main antagonists in Season 2, he is finally defeated in "Obsesstions of Doom", and stripped of his diplomatic immunity.
 * Grim Reaper (Lance Henrikson) - joins with Doom
 * Dr. Octopus (Corey Burton)
 * Mastermind (Andre Stojka)
 * Bullseye (Steve Blum)
 * Eddie Brock/Venom (Travis J. Gould)
 * Chameleon (Andre Soliquizo)
 * Living Laser (Nolan North)
 * Baron Mordo (Michael Dorn)
 * Emma Frost (Kari Wahlgren)
 * Crossfire (Neil Ross)
 * Surtur (Rick D. Wasserman) - revealed to be freed by Kurse to keep Thor in Asgard to keep him in power, reimprisoned with the help of Thunderstrike and Beta Ray Bill.
 * Enchantress (Kari Wahlgren) - trapped under Surtur's control, the Enchantress serves as the Dragon to the Fire Giant for Seasons 2 until she is finally killed by Thor and freed from her spell upon her resurrection.
 * Ultron-7 (Tom Kane) - having rebuilt himself yet again following his destruction at the hands of Hank Pym.
 * Skrulls:
 * Veranke (Elizabeth Daily) - Queen of the Skrulls, and one of the main antagonists from Season 2.
 * Criti Noll (Brian Bloom) - The Captain America Imposter, and Veranke's second-in-command of the Skrull Fleet.
 * Super Skrull (Kyle Hebert) -Veranke's third-in-command of the Skrull Empire, and leader of the Super Skrull army.
 * Kree:
 * Kalum Lo (Fred Tatasciore)
 * Ronan the Accuser (Keith Szarabajka)
 * Sentry-459
 * Supreme Intelligence (David Kaye season 2, Dee Bradley Baker season 3)
 * Yon-Rogg (Fred Tatasciore)
 * Galactus (Leonard Nimoy) - takes over as the main antagonist of the season 2 finale, after being imprisoned in the boiler room by Kang

Season 3:

 * Thanos (Michael Ironside) - the main antagonist, gone on a quest to search for the Infinity Gems. When he defeats his enemies, he snaps their necks, he also uses his powers to drain the victims's souls from their bodies and absorbs them into his being in order to amplify his powers. His victims will include the Guardians of the Galaxy, Supreme Intelligence, Veranke, Michael Korvac, and Yon-Rogg.
 * Brian Banner/Demon Hulk (Udo Kier, Keith Szarabajka) - Bruce Banner's father, and has the same past as David Banner from Hulk
 * Egghead (John DiMaggio) - he hates Hank very much and decides to expose Ultron as Hank's project, courtesy of Tony Stark
 * Mandarin (Paxton Whitehead) - asks for Living Laser, Power Man, Swordsman, the freed Enchantress and Executioner's help for conquest by finding the 10 rings
 * Living Laser (Nolan North)
 * Power Man (Robert Patrick)
 * Swordsman (Jeffrey Tambor, matches Crazy Quilt's tone)
 * Enchantress (Kari Wahlgren)
 * Executioner (John DiMaggio)
 * Magneto (Ron Perlman) - wants to raise Quicksilver and Scarlet Witch in behalf of the Brotherhood
 * Masters Pandemonium (Pat Frayley) - He was originally an actor who lost an arm in a car crash, and made a pact with Mephisto to regain his limb. Mephisto instead took the man's other three limbs, then replaced them all with demonic grafts. He was also given a hole in his chest in the shape of an inverted five-pointed star, and the ability to survive despite this hole in his chest. He was also given the ability to command the demons inside him. He seeks the five beings possessing parts of his fragmented soul

Other villains

 * Absorbing Man (Rick D. Wasserman)
 * Annihilus (Kevin Michael Richardson) - revealed to have made a deal with Kang to cause the attack on 42
 * Armadillo (Ogie Banks)
 * Bi-Beast (Wade Williams)
 * Blank (Richard McGonagle)
 * Blizzard (Troy Baker) - killed by the Annihilation Wave in "Assault on 42"
 * Circus of Crime:
 * Bruto the Strongman (Richard McGonagle)
 * Cannonball (J.B. Blanc)
 * Clown (Charlie Adler)
 * Fire-Eater (Ogie Banks)
 * Flying Gambonnos (Jeff Bennett and Maurice LaMarche)
 * Livewire (Cindy Robinson)
 * Princesss Python (Tara Strong)
 * Ringmaster (Corey Burton)
 * Crossfire (Neil Ross)
 * Doctor Octopus (Corey Burton)
 * Galactus (David Kaye)
 * Glenn Talbot (Troy Baker)
 * Graviton (Fred Tatasciore)
 * Griffin (Fred Tatasciore)
 * Heralds of Galactus
 * Air-Walker (Daniel Riordan)
 * Firelord (Khary Payton)
 * Stardust (Andrea Baker)
 * Terrax (Kevin Grevioux)
 * Michael Korvac (Troy Baker)
 * Kurse (Clancy Brown) - posed as Odin in Season One, and 2 and released Surtur!
 * 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 (Phill LaMarr)
 * Constrictor (Cam Clarke in Season 1, Troy Baker in Season 2)
 * Death Adder (Dee Bradley Baker)
 * 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 (John DiMaggio)
 * Scorpion (John Kassir)
 * Technovore (Dwight Schultz)
 * U-Foes:
 * Vector (Cam Clarke)
 * Ironclad (Kevin Michael Richardson)
 * Vapor (Colleen O'Shaughnessey)
 * X-Ray (Dee Bradley Baker)
 * Ultimo (Peter Stormare)
 * Whiplash (Tara Strong) - meets Venom, but refuses to join!
 * Wrecking Crew:
 * Wrecker (J.B. Blanc)
 * Bulldozer (James C. Mathis III)
 * Piledriver (Nolan North)
 * Thunderball (Gary Anthony Williams)
 * Zzzax (Dee Bradley Baker)