The Mighty Avengers were created as the New York branch of the 50-state Initiative, though this team unlike the other Initiative teams serves all of the nation and the world, not just their respective state.

ULTRON'S RETURN

During a battle against the Mole Man, Iron Man's armor went haywire and turned him into a woman. Mentally and physically. That women he was turned into was none other than Ultron.

Thinking Tony was dead, the Mighty Avengers battled Ultron. During the battle Ultron, using her internal computer systems, activated a satellite that could control the weather. Creating natural disasters all around the world. The Mighty Avengers had to resort to getting the help of Hank Pym, Ultron's creator.

Ultron then killed Sentry's wife. Which enraged Sentry deeply. During their battle the rest of the Mighty Avengers battled an armada of Iron Man armor's which were under the control of Ultron. In the meanwhile Hank began creating something to stop Ultron. Sentry was about to kill Ultron when Ms. Marvel stopped him, knowing if he killed Ultron, then there would be no hopes of getting Tony back.

A microscopic Ares was then released into Ultron to release a virus that would hopefully kill Ultron and bring Tony Stark back. He succeeded barely and Ultron was seemingly killed, returning Tony to his rightful body and mind.

Skrulls and Symbiotes

As Tony rests, Spider-Woman appears at his side, holding the dead body of the skrull Elektra. They discuss for a while about what this means, and Tony asks her to join the Mighty Avengers so that she can find the skrull in the team. She does so, but as he introduces her onto the team (some members less happy about it than others) a symbtiote bomb is dropped on New York.

The team goes to help, and team up with Luke Cage. When Wasp grows in size, she, Black Widow and Spider-Woman are taken over by symbiotes. In the end, Iron Man discovers a cure for the symbiote virus and releases it on New York.

They discover that the bomb was released in Latveria, and they all attack Doom's castle. But when Iron Man and Doom fight, they activate Doom's time machine, and as Sentry goes in to save Iron Man, the three are teleported to the past.