The other half of one of the most notable tag teams in Marvel Comics history, Skurge would almost be a given if Amora was in the mix. Unlike the villain pairings in many other comic book sequels, this one would be a natural way to get more bad guys into the movie.
Like Loki, the Executioner traces some of his heritage to the frost giants, and they’ve already been introduced in the film series. And it goes without saying he’d make for some great visuals. Get a big, intimidating actor to play him, shave his head, craft an awesome double-bladed axe for him to wield and you’re good to go.