Here is a short breakdown of creating the Zombie King metahuman character.
Step 1 was to create a base character in Metahuman creator. I chose one of the presets and modified it to look like an older man.
The character was supposed to look less like a typical zombie with rotten flesh, but rather retain a "normal" human face and appear as if he was burned. So I adjusted the face a bit and then created a morph target in Unreal Engine with the help of the Mesh Morpher plugin.
The texturing was done in Substance Painter. I used the metahuman normal map as a base and added different layers of procedurally generated and hand painted masks and textures to achieve the burnt look.
Here is the original base character on the left, and the modified mesh and textures on the right:
The outfit was designed by a digital fashion artist, which I then textured, rigged and skinned to the metahuman character.
Finally, I added some props and cloth simulation in Unreal Engine.
Cheers!