Writer and director Joss Whedon confirmed in a interview with IGN that Scarlet Witch and Quicksilver will indeed be introduced inThe Avengers 2, and that Tony Stark will be back for more avenging action as well. He revealed in the interview why he’s including the brother and sister pair in the movie:
“You know, they had a rough beginning. They’re interesting to me because they sort of represent the part of the world that wouldn’t necessarily agree with The Avengers. So they’re not there to make things easier. I’m not putting any characters in the movie that will make things easier.”
The next subject he is asked about the return of Tony Stark’s Iron Man. This next quote contains spoilers for Iron Man 3, so if you haven’t seen the third film yet, then you might not want to read ahead.
“Well, I feel like in Iron Man 3, even though he said, ‘I’ve changed’ — he blew up his remote suits, but I don’t think anybody thinks he doesn’t have one anymore. The question is, if The Avengers are called, does he show up? And the answer is, ‘Yes!’”
So Iron Man will definitely be back in Avengers 2! Of course it’s not really clear in what capacity he’ll return, or even if he’ll be played Robert Downey Jr.
The Avengers 2 is scheduled to assemble on May 1st, 2015.