Avengers : Season 1, Episode 20: "The Casket of Ancient Winters"

"The Casket of Ancient Winters" - On the hottest day of the year, an ancient artifact is found…and a cold wind blows. An ancient Asgardian relic called the Casket of Ancient Winters has been opened, and the entire planet goes into a deep freeze. But as the rest of the Avengers deal with an invasion of Dark Elves and demons, Iron Man and Thor must put aside their differences to battle Malekith the Accursed.

Avengers : Season 1, Episode 19: "Widow's Sting"

"Widow's Sting" - Hawkeye’s still out to take down the Black Widow, and he’s going to shake down every HYDRA agent on the planet to do it. Which is starting to tick off Nick Fury. Both Iron Man and Fury order Hawkeye to back off, but hey…it’s Hawkeye. So with S.H.I.E.L.D. babysitter Mockingbird at his side, Hawkeye infiltrates Hydra Island to take the fight right to the Black Widow. Will Hawkeye finally trust somebody enough to save his life?

Avengers : Season 1, Episode 18: "The Kang Dynasty"

When the planet is threatened by super villains, time traveling conquerors, alien invaders, mythical monsters or mad robots bent on the total destruction of humanity...when the forces of evil are so overwhelming that no single hero has the power to save the world, when there is no hope left…the AVENGERS ASSEMBLE!

Tune into "The Avengers: Earth's Mightiest Heroes!" Sundays at 10:00 a.m. ET on Disney XD for all the action and excitement, Marvelites, and check in to Marvel.com for interviews, videos and more! To top it all off, now you can stream episode 18 right here!

Here's the synopsis of episode 18:

"The Kang Dynasty" - Kang the Conqueror’s takeover of Earth is well underway, and the Avengers launch a last ditch offensive to stop the time traveler’s plans. What hope do the Avengers have? Kang’s Damocles Base has the power to destroy the world, his technology is more advanced than anything Iron Man has ever seen, and his personal guards are unstoppable. But what secret is Kang hiding that could lead to his downfall?

Avengers :Season 1, Episode 17: "Come the Conqueror"

"Come the Conqueror" - Kang’s invasion of Earth begins in earnest! A fleet of ships from the future unleash war on the planet, and the Avengers are helpless to stop it. But while Iron Man searches for Kang himself, Captain America takes charge of the Avengers…but to fight a war, you need an army. And Wasp knows where Cap can get one. Welcome to the other dimensional prison called 42, maintained by a robot called Ultron.

Avengers: Season 1, Episode 16: "The Man Who Stole Tomorrow"

"The Man Who Stole Tomorrow" - Kang the Conqueror has arrived in the 21st century with two goals…destroy Captain America and take over the world. The Avengers aren’t about to let either happen...until Kang explains why. Because in the near future, the Earth will be destroyed. Kang has come to save the world, and the Avengers are standing in his way.

Avengers : Season 1, Episode 15: "459"

"459" - Something has fallen to Earth...something here to destroy us all. A Kree Sentry has arrived, heralding Earth's entry into an interstellar war between two alien empires. And if Ant-Man and the Wasp don't stop it, humanity is doomed. But they may have an ally living among them...Enter: Captain Marvel.

Avengers : Season 1, Episode 14: "Masters of Evil"

"Masters of Evil" - Zemo! Enchantress! Executioner! Abomination! Wonder Man! Crimson Dynamo! Individually they are the most powerful super villains on the planet. Together, they are unstoppable. Avengers Mansion is laid siege and one by one, the Avengers fall. And with the most powerful of them defeated, what hope do Black Panther and Hawkeye have?

Avengers : Season 1, Episode 13: "Gamma World Part Two"

"Gammaworld Part Two" - The Leader’s master plan has been unleashed, and half of North America has been turned into Gamma Monsters, including the Avengers! In 24 hours, the entire world will be under the Leader’s control. Our only hope? Hawkeye. His only hope? Finding the Incredible Hulk and convincing him to stop the Leader from turning Earth into Gamma World.

Avengers : Season 1, Episode 12: "Gamma World Part One"

“Gammaworld Part One” - A dome of gamma energy envelops the Cube, turning everyone inside of it into a Gamma monster. S.H.I.E.L.D. and Doc Samson know that the Leader and a host of super villains are inside…but worse, the dome is expanding. The Avengers are going in, but they’re not prepared for what they find inside. Meanwhile, Hawkeye catches up to the traitorous Black Widow.

Avengers : Season 1, Episode 11: "Panther's Quest"

"Panther's Quest" - The Prince of Wakanda has been stalking the Avengers for weeks, and now the Black Panther strikes! The Panther wants the Avengers' help in taking back the throne of Wakanda from the vicious Man-Ape. The problem is, they have to go through the Wakandan army, HYDRA, and Klaw to do it.

Avengers :Season 1, Episode 10: "Everything is Wonderful"

A business decision by Tony Stark leads rival Simon Williams to go to extreme measures for revenge…he seeks help from the Grim Reaper and A.I.M. Now transformed into the ionic powered Wonder Man, Simon takes the fight back to Tony Stark! But the only one there to defend Tony is the one Avenger who dislikes him the most…Ant-Man. Has Tony Stark changed? Plus! Wasp and Thor versus M.O.D.O.C.!

Avengers :Season 1, Episode 9: "Living Legend"

Living Legend: On the hunt for the Hulk, the Avengers stumble across another hero, long thought lost…Captain America! Cap’s been frozen since WW2, kept alive by the Super Soldier Serum. Now a man out of time, Captain America figures the world doesn’t need him anymore…but he’s wrong. Because Cap’s old enemy Zemo is alive and well, and wants nothing more than to put Cap back on ice, even if he has to go through the Avengers to do it.

Avengers : Season 1, Episode 8: "Some Assembly Required"

Season 1, Episode 8: "Some Assembly Required"

"Some Assembly Required" - The Avengers have assembled, but calling themselves a team is different than BEING one, especially when you've got the Hulk as a member. As Iron Man introduces the Avengers to Avengers Mansion, the Hulk is ready to smash them all... with a little magical push from the Enchantress. The Avengers may be over before they start as they take on one of their own.

Avengers : Season 1, Episode 7: "Breakout Part Two"

The Super Villain breakout has begun, and it's everything our heroes can do to stay alive! The man called Graviton is now free. He's after Nick Fury… but he’ll destroy the world to get to him.

Avengers : Season 1, Episode 6: "Breakout Part One"

Breakout, Part 1: Iron Man, Hulk, Thor, Ant-Man and Wasp have defeated some of the most powerful, Super Villains on the planet. But now, on a day like none other, their prisons open wide. Our heroes' only hope is to band together…to become the Avengers.

Avengers : Season 1, Episode 5: "The Man in the Ant Hill"

When the planet is threatened by super villains, time traveling conquerors, alien invaders, mythical monsters or mad robots bent on the total destruction of humanity...when the forces of evil are so overwhelming that no single hero has the power to save the world, when there is no hope left…the AVENGERS ASSEMBLE!

Tune into "The Avengers: Earth's Mightiest Heroes!" Sundays at 10:00 a.m. ET on Disney XD for all the action and excitement, Marvelites, and check in to Marvel.com for interviews, videos and more! To top it all off, now you can stream episode 5 right here!

Here's the synopsis of episode 5:

"The Man in the Ant Hill" - Three tales to astonish, featuring Ant-Man and Wasp! When scientist Hank Pym obtains a rare sample of Vibranium to study, the villainous Klaw comes to steal it…but he’s not ready to enter Ant-Man's world. Then, the wondrous Wasp takes on Whirlwind! And finally, take a tour of the Big House, the world’s smallest super villain prison. Plus, welcome to Wakanda, the most powerful nation on Earth…you’re just in time to see the fall of the Black Panther.

Avengers : Season 1, Episode 4: "Meet Captain America"

"Meet Captain America" - In the closing days of World War II, Captain America and Bucky join forces with Jack Fury and his Howling Commandos for a final confrontation with the Red Skull and his HYDRA forces! But as the battle unfolds, they’re being watched by a visitor from the future. His name is Kang the Conqueror, and he’s on a mission to save the world.

Avengers : Season 1, Episode 3: "Hulk Versus the World"

“Hulk Versus The World” - When Bruce Banner heads to Vegas to track down an escapee from the Super-Villain prison known as the Cube, he’s forced to transform into the incredible Hulk to take on the Absorbing Man. But to make matters worse, Thunderbolt Ross and his Hulkbusters are on the scene with orders to take the Hulk down. And even if the Hulk can defeat Absorbing Man and the Hulkbusters, can he survive S.H.I.E.L.D.’s most dangerous agents… Hawkeye and the Black Widow?

Avengers : Season 1, Episode 2: "Thor the Mighty!"

“Thor the Mighty!” - The villainous Wrecking Crew are tearing through New York City, and the only thing that’s standing in their way? The Mighty Thor! But when Thor is called back to Asgard by his father Odin, he’s forced to face off against an army of Frost Giants led by the evil Loki…Thor’s adopted brother. But even if Thor wins the battle, he may have lost more than he realizes, for nothing is ever as it seems with Loki…

Avengers : Season 1, Episode 1: "Iron Man is Born!"

“Iron Man Is Born!” - When the villainous organization known as HYDRA attacks the United Nations, the fate of the world’s leaders is in the hands of Iron Man! But Tony Stark may have met his match as HYDRA unleashes the Dreadnoughts against him! Iron Man has to overcome HYDRA, but is the world peacekeeping force known as S.H.I.E.L.D. any better? Plus, S.H.I.E.L.D. Director Nick Fury fights alone when the Grim Reaper infiltrates the super villain prison known as the Vault.