Thanos
The antagonist of the film, Avengers: Infinity War and its unnamed sequel (during the time of writing this) who is the leader of the Chitauri, the Black Order and the Outriders. He was the man pulling the strings in several Marvel movies before this: in Avengers, he provided Loki with the Sceptre and an army. Also, in the Guardians of the Galaxy, he was Ronan's boss. In Avengers 3, he kicked his plans for getting the Infinity Stones and fought against the Avengers. He was also popularized by a trend of memes called, "Thanos Did Nothing Wrong", in which people post memes proving his point of view was right. In the comics, he was created by writer/artist Jim Starlin and first appeared in The Invincible Iron Man #55(February 1973). In the movies he was portrayed by Josh Brolin.
Thanos is as good as the Joker from the Dark Knight, if not better.
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