Making the Reliefs on the Front
First I threw some skulls and bones on a plane in 3ds Max with the Paint Object feature. Then I modeled a very simple guillotine and gallows (Fig.05).
After I exported these to ZBrush I used the MRgbZgrabber to capture alphas from these models. Later I combined those in Photoshop and got the result you can see in Fig.06.
These were the alphas I used to make the reliefs on the front with Projection Master. After these were applied to the model I used the Inflate and Clay brushes to add more depth to them and made the cuts deeper with the Dam Standard brush. The high poly part was done (Fig.07).
Texturing Part 1: Base Texture
I wanted the armor to look worn and very old, and the skin to be undead-like. I always start the texturing by defining the main colors and materials. In ZBrush I used materials similar to what I wanted my end result to look like. With a soft Standard brush I established the base colors for the face and armor. I painted the mouth and nose areas using more red because of the blood and veins and the bony parts using more yellow. I used Cavity masks to fill the crevices with darker colors. With this method I had a solid base to start from.
I painted the skin to be a natural color first and later changed it to "undead" in Photoshop. I just dragged textures of metal on the armor to give it a base color. After this I added textures from photos with Spotlight to add details and break up the surface. When I wanted to work on the whole texture at once - to adjust the levels or the hue, for example - I created a texture from polypaint, exported that to Photoshop and made the adjustments there. After that I re-applied the modified texture. If the resolution of the texture is high enough it stays the same quality.
I used Zapplink to add small details and project photos on areas like the lips. On the armor I used brushes with scratch alphas and the lighten paint mode in ZBrush to add wear and tear to the texture. Where the different subtools connected to the main mesh I painted rust drips and colored it darker so they connected better to each other.
This was the base texture I used to make all the other maps (Fig.08).
After the high poly mesh was done I decimated all the subtools with Decimation Master so they had a lower poly count while keeping the details. I used this mesh as a reference for my low poly. I started from scratch rather than refining the geometry. My high poly geometry's topology usually becomes a mess at the end of the sculpting session since I like to use the Pinch tool a lot. I used Topogun to get a base geometry for the low poly. When this mesh was done it needed to be optimized and cleaned up. I prefer to do this in 3ds Max. I removed edge loops, collapsed edges to reduce poly count. I kept in mind however that the face has to deform correctly in animation, so I set up the edge loops there properly.
My goal was to create a very detailed model so I was not worried about the poly count that much, but I wanted to put it into a game engine so it had to be reasonably low. When building the low poly mesh the most important thing I had to keep in mind was the silhouette because the normal map can't simulate the outlines of the model, only the inner details. A handy trick I often use is to make a material animation: on the first frame the material is normal and on the last one it's completely black so I can swap between silhouette and the normal view. When I reached about 16,000 triangles, including the chains, the low poly was done (Fig.09).