Casting Ava DuVernay's New Gods
5. Kalibak - Manu Bennett
While Bennett may be well-known for playing Deathstroke in the CW's Arrowverse, DC seem to have no problem casting actors in multiple of their own projects, so bringing him into the world of the New Gods shouldn't pose an issue.
The menace and underlying charisma that the actor brought to Slade was great, but it is his performance in The Hobbit that would provide a good basis for the character of Kalibak (Darkseid's more monstrous son).
Azog, his character in the Tolkein-inspired movies, was a warrior orc who was as cruel and as isolated as Kalibak usually is, both characters being presented as the outsiders of their kind but also the most skilled warriors - meaning that, in essence, Bennett has already played many of the shades Kalibak has to offer.
As such, he would be great in the role.