Loki gave the Tesseract to Thanos in order to save his brother Thor. He tricked the mad titan into thinking that he's dead. Loki will do anything in his hands to save the Avengers and Thor from getting killed by Thanos. He made a promise to his brother after all. In other words: 2012 Loki saves Infinity War Loki [This one shot contains script from the Loki series, Infinity War and Endgame! All characters are owned by Marvel!]