Final artwroks and other variations
Here is the final version of the concept I rendered from ZBrush:

This is the poster version for a potential cover of a graphic novel:

And another 'vintage' version just for fun:

And this is the final outline before colours:

Collaboration with J. Hill
I also did a collaboration with J. Hill covering some other tips and tricks of the process of creating the final image I showed at the beginning of the video. Here is the link to that collaboration:
Comic-style outlines with geometry in ZBrush
In this short video tutorial, I’m going to share a quick tip to create comic-style outlines in ZBrush using geometry. You can achieve a very decent ‘comic look’ using the Comic material I shared in this tutorial, but this additional tip allows you to control the outline to make it more consistent or even ‘sculpt the thickness’ yourself… Also, it works as an outline on any material so you don’t need to rely on the comic shader ;)
Check it out