It's been rumored for a few months, but now we have confirmation that Game of Thrones actor Ciaran Hinds will be playing Steppenwolf in the upcoming Justice League movie. The actor confirmed the casting in an interview with The Independent last week.
The character was teased in a deleted scene from Batman v Superman: Dawn of Justice as the one pushing Lex Luthor's buttons.
Steppenwolf was CG in the deleted scene, something that will continue in Justice League according to Hind.
Basically they're going to construct something, digitally, and then they will use my eyes and mouth.
He's old, tired, still trying to get out of his own enslavement to Darkseid, [but] he has to keep on this line to try and take over worlds.
Justice League will be in theaters November 17th.