As 'Iron Man 3' gets set to hit theaters this weekend, Joss Whedon continues to tease 'Avengers 2' with public comments. Just a few days after he mentioned he's adding a brother/sister team to the upcoming sequel, comes Whedon's comments on Robert Downey, Jr.'s potential retirement and the "big finale" coming in 'Avengers 2' as the superhero team gets ready to face off against Thanos.

There has been plenty of talk over the past few weeks about whether Robert Downey, Jr. was done playing Iron Man. It doesn't sound like Downey himself even knows the answer but Whedon was asked about what would happen to 'Avengers 2' if Robert Downey, Jr. decided to hang up the Iron Man suit. Says Whedon:

I want him to play it forever. At the same time, if Robert decides to hang it up, he has a perfectly good excuse.

A good excuse for sure, but it would also throw 'Avengers 2' into something of a tailspin if there was no Iron Man. We certainly couldn't imagine another actor playing that role but you can't really have an 'Avengers' movie without Iron Man, can you?

As for the other big part of 'Avengers 2,' Whedon talked about Thanos, the villain teased at the end of 'The Avengers' and the central antagonist at the heart of Phase 2 of the Marvel Cinematic Universe. So how big will the threat be? Explains Whedon:

Well, Thanos is more powerful. He is so powerful, he is not someone you can just trot out and punch him. Like he did in the comics, you want him to be threading through the universe and to save the big finale for the big finale. He is definitely a part of what I've got going on. The thing about the Avengers is that they are very powerful, but they're not very stable. So, there will definitely be some people that will shake them up in the next installment.

That instability was a big part of the original 'Avengers' and it'll be interesting to see how Thanos and his minions exploit that over the next few films. It certainly sounds as though Thanos could be seen (or at least his presence felt) through some of the upcoming Marvel movies in advance of 'Avengers 2' setting up the so-called "big finale."

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