Iron Man comes face to face with Galactus who is determined to make Earth his next meal, but Galactus finds a new herald in Tony Stark when he's led to another planet... one that is under the protection of the Guardians of the Galaxy! Now the rest of the Avengers must team up with the Space Knights to stop Galactus from feasting and save Tony!
When Red Skull comes crashing to Earth with a fleet of alien ships chasing him, the Avengers learn there's a villain in their midst a thousand times more dangerous than the Cabal ever was: Thanos! Earth's Mightiest Heroes are forced to face the fact they're big fish in a small pond -- and this new villain wants to conquer the entire ocean! Will the mightiest superheroes on Earth be able to stop the super-villain of the galaxy... before he succeeds in becoming all-powerful?
In a 'flipped reality,' the Avengers discover that their world has been reshaped by the Reality Stone, wielded by the Squadron Supreme. In this new reality the Squadron Supreme have made themselves the heroes and the Avengers the villains! Find out if the Avengers can take down the Squadron Supreme and prove that they're the real heroes.
Now that he's an Avenger, Ant-Man "cleans his ledger" by bringing down bad guys that he's previously built tech for. However, his quest for redemption forces other Avengers to face the burdens of their past and when they discover Dr. Spectrum is on Ant-Man's ledger, the Avengers are forced to face one of the most powerful members of the Squadron Supreme before he destroys the world.
The Avengers try to stop A.I.M. from stealing high-tech weapons from the future ever since it was discovered that they upgraded the gear of Whiplash and Spymaster. Their fight with A.I.M. attracts the attention of the 30th-century warlord Kang the Conqueror since it was his technology that A.I.M. used as he takes control of the A.I.M. Agents present.
The President has signed the New Powers Act in response to the Terrigen Fog creating new Inhumans and Truman Marsh is assigned to be the Avengers liaison to the government. Meanwhile, scientists backed by HYDRA enter a gamma storm with a stolen spaceship and are transformed into the U-Foes where they plan to take over HYDRA when Baron Strucker hasn't returned.
With the Avengers disassociated with the government amongst the Inhuman Registration Act, Truman Marsh assembles The Mighty Avengers (consisting of Ant-Man, Black Panther, Captain Marvel, Ms. Marvel, Red Hulk, Songbird, and Vision) to take their place where they first fight against Baron Strucker and HYDRA with the Avengers after them. Later on, the Avengers work to keep the Mighty Avengers from taking the Inhumans Haechi, Flint, and Iso into custody.
As the Avengers find a way to return Iron Man to their reality without bringing Ultron along, they managed to prevent Ghost from stealing Stark Industries technology at the Stark Expo. After swiping the prototype Arc Reactor, the Leader heads to the Wakandan Consulate to steal the Vibranium there with his army of Humanoids. When a guilt-ridden Thor helps Black Panther take down the Leader when the Avengers arrive, the Leader summons his new incarnation of the Cabal (consisting of Arnim Zola, Enchantress, Executioner, and Kang the Conqueror) to fight the Avengers while taking advantage of Iron Man not being there.
When the Avengers trapped by the effects of the Static Expander made from the stolen Stark Industries technology, Black Panther escapes with the stolen Vibranium and avoids Executioner in order to get a team to help him. Upon awakening Vision who helps him fight Executioner and his pet Asgardian dire wolf as well as Enchantress reclaiming the Vibranium for the Leader, Black Panther and Vision must lead Ant-Man, Captain Marvel, Ms. Marvel, and Wasp into finding the Avengers so that they can stop the Cabal.