Crimson Void

The Crimson Void are an experiment created by the dreadlord Varonoth. The creation process involved the raging brute, Dathrak, who had been manipulated and captured by the daring dreadlord. Dathrak's energies were siphoned and stored within regular Voidwalkers, turning them into red raging Voids that could have been the equal of Dathrak in the past.

Crimson Voids behave exactly like Dathrak in that when they're faught, they have to be taken care of quickly or risk being overwhelmed by sheer brute strength. Crimson Voids were mass-produced and scattered all across Azeroth by Varonoth and since Dathrak's escape, have begun being hunted by the very being they were created from.

Rage
Like Dathrak, a Crimson Void has uncontrollable anger issues. The angrier one of these monstrosities get, the stronger they become. Some of them even fuse together to create an even bigger, stronger Crimson Void if they're in groups. A Crimson Void, much like Dathrak, cannot handle Arcane very well and as such, being bombarded with it causes their rage and energy to drain rapidly.