Marvel Warning: There are minor spoilers ahead for "Avengers: Infinity War." "Avengers: Infinity War" will leave you with plenty of unanswered questions, but there's one detail which may have left you perplexed unless you did a recent binge of the Marvel Cinematic Universe catalog.See the rest of the story at Business InsiderNOW WATCH: This incredible animation shows how humans evolved from early lifeSee Also:‘Avengers: Infinity War’ ends on a cliffhanger that will leave you devastated — here’s what it means for the sequelThe only Marvel movies you need to watch before seeing 'Avengers Infinity War''Avengers: Infinity War' has one end-credits scene — here’s what it means for future Marvel movies