The Wall Street Journal has confirmed in an interview with Geoff Johns that the man behind the mask (Deathstroke) is none other than Joe Manganiello and that he will be the villain of the upcoming solo Batman movie.
He didn’t make any comments about Deathstroke will appear in Justice League, though the short clip of the character was seen filming on one of the sets for the film.
No official release date has been announced for the project, though Affleck previously said he wouldn’t begin production until the script was completed. Warner Bros. set release dates for two untitled DC projects on October 5, 2018 and November 1, 2019, meaning the film could take one of those dates.
Created by Marv Wolfman and George Pérez, Deathstroke is a famous mercenary in the world of DC Comics who has gone toe-to-toe with the Dark Knight on multiple occasions and actually beaten him in hand-to-hand combat more than once.