Despite a small camp of people who still want to believe the third Avengers will be based on World War Hulk, most comic fans are able to recognize the Infinity Gauntlet clues and are looking towards Thanos as the big bad in the Marvel Cinematic Universe.
We’ll get to see more of Thanos in Guardians of the Galaxy, and in an interview on Total Film Kevin Feige confirms that all of this Thanos build-up is leading to a confrontation with The Avengers in a future movie (not Age of Ultron):
“If you remember we had a tag scene in Thor: The Dark World where Benicio Del Toro showed up for the first time as The Collector, so that was our way of saying the Guardians and the other Marvel characters inhabit the same reality and the same universe. In particular, there’s a villain in this film, that comic fans know as Thanos, that moviegoers will begin to learn more and more about in the coming years. He appeared at the very end of the first Avengers film, when he turned into camera and smirked, and we realised he was the person behind the alien army that Loki teamed up with to terrorise New York City, and that the Avengers had to fight.
“We see him again in this movie [Guardians], we learn a little bit more about him in this movie, and he – and his band of followers – is the biggest piece of connective tissue that will eventually lead us back into Avengers films in the future.”
If you’re curious about what these clues are, we’ve put together a little feature showing how Thanos and Guardians of the Galaxy will link up with the overall Marvel Cinematic Universe.