Twitch reports that Kristen Stewart is now in the mix for the role of female protagonist Kei. I'm still on the fence about Stewart in general with her terrible performances in Twilight but Huntsman could change my opinion.
A rumored offer has gone out to Helena Bonham Carter (Dark Shadows, Deathly Hollows, Fight Club) for the role of Lady and Keira Knightley (Pirates 1-3) had been linked for an unknown role. Garrett Hedlund (Tron Legacy, Troy) is up for the hero role of Kandea and Gary Oldman (Dark Kight) has been offered the role of the Colonel. While Ezra Miller (We Need To Talk About Kevin) and Alden Eherenreich are up for Tetsuo.