Thanos will be the motivation for the Avengers’ return in Anthony and Joe Russo’s upcoming Avengers: Infinity War.
With that said, Thanos will be the most powerful Marvel villain yet and will be played by Josh Brolin through motion capture digital effects and voice acting. He was previously revealed in the after credits scene for The Avengers with another short appearance in Guardians of the Galaxy.
You can see Brolin in a picture below, wearing a purple motion capture suit and filming test footage with the Russo brothers. The picture was taken at Pinewood Atlanta Studios, where Avengers: Infinity War will be shot.
The film will be released May 4, 2018.
Source: The Russo Brothers