Most likely, Matthias Schoenarts will play a version of Krem of the Yellow Hill, who joined the Brigands, an extremely violent group that aims for all kinds of genocide.
He is able to defend against the use of the Mordru Globe, which is powerful even against someone like Supergirl. While Krem doesn’t have the same powers as many others in the DC Universe, he is a formidable character who has no problem killing.
Whether James Gunn and DC take on this character remains to be seen, but the use of the Mordru Globe alone could spell interesting aftereffects in the DC world.