The single largest mod for Age of Empires II HD. Made specifically for The African Kingdoms. Other versions may or may not be supported.
Coming in the distant future, the full Age of Bloodshed Campaign. Age of Bloodshed 1.07 will give you some campaign missions, but much farther on, when the full campaign is complete, you will all get to enjoy the blood ocean textures.
I think what you need is a dedicated hell faction
I've been trying to code one, but African Kingdoms is having a hard time accepting new civilizations.