Casting HBO's Justice League Dark

Starting with the obvious: Nicholas Hoult would work so well visually as Deadman. He has the right build, doesn't have long hair (meaning it wouldn't look weird to see him without any), and can pull off the white make-up look, as proven by Mad Max: Fury Road.

Performance-wise it's a similar story. Hoult is known for playing more timid characters, though he got far enough in the runnings to play Batman to show that branding him in such a way might be unfair.

In short, he looks the part and can play the part well, what more convincing does one require? I mean, it's not like he'll be making more X-Men movies anytime soon.