According to IGN on July 30, Joss Whedon says that the villain Ultron in “Avengers: Age of Ultron” will indeed juice things up for The Avengers in this film because he’s been a “thorn in their side” historically in the Marvel comics. Whedon even stated that he had pitched the Ultron character before saying yes to the first “Avengers” film.
“I was pitching Ultron before I took the job on the first movie. I was like, ‘I don’t know if I want to do this, but for the second one, you should totally do Ultron.’ Because he’s been a thorn in their side as much as any other character over the years and particularly back in my history”.
It looks to be that Ultron won’t be the typical character that some heroes face and can take out in no time flat.
“He’s somebody who can juice things up and he’s a real problem for the Avengers. That’s not always easy to find. It’s not like the Vulture is really going to give them a hard time for 20 minutes”.
It had already been stated at the San Diego Comic Con that the creation of Ultron won’t be of that Hank Pym/Ant-Man, but there has been speculation of who it could be.