Malekith

"'Hey, Loki! Thanks for hogging my spotlight, you jerk!' -Malekith"

Malekith the Accursed is the leader of the Dark Elves and the main antagonist of Thor: The Dark World.

Early Life
Malekith, born on Svartalfheim, was the warmongering leader of the Dark Elves. He sought to use the Aether, a weapon forged from the Reality Stone, to plunge the Nine Realms into darkness during the Convergence. However, his plans were made known to the Asgardians, and when the Convergence occurred, the Asgardians and Dark Elves clashed in the Dark World. The battle ended with the Asgardians capturing the Aether, and Malekith destroying most of his people and entering hibernation.

How Thor: The Dark World Should Have Ended
At the Villain Pub, Loki explains that he was forced to help Thor defeat Malekith. Shortly afterwards, Malekith arrives and complains that Loki hogged his spotlight. However, Loki simply points out Malekith's generic plans and embarrassing defeat at the hands of "two human scientists and two brainless interns carrying nothing but tripods" and calls him an amateur. Malekith then takes his leave.

Villain Pub- The Dead Pool
Despite having been kicked out of the pub for being a generic villain, Malekith joins the other Marvel antagonists in betting on who Thanos will kill in Infinity War. When the Joker claims that Marvel's good guys always live, Malekith points out that not all of them survive.