This post has not been vetted or endorsed by BuzzFeed's editorial staff. BuzzFeed Community is a place where anyone can create a post or quiz. Try making your own!Buzz·Posted on May 11, 2015Vote In Round 4 Of April Madness: The “Avengers” EditionWho is the greatest Avenger of them all?by colleensteinawayCommunity ContributorLinkFacebookPinterestTwitterMail Voting for Round 4 will end on Sunday, May 17, 2015. Round 5 will begin Monday, May 18, 2015.Check out what happened in the earlier rounds:Round 3Round 2Round 1