As with the Hellboy Speedpaint, I've left the toolbox in view so that you can which tools I'm using and when. For the most part I'm using nothing but the Brush tool at about 15% opacity, switching between white & black.
I've included a few commonly asked questions here for quick reference. Hopefully, you'll find this useful.
P.S. I made the eye smaller after working on Part I but I didn't record it. I used the exact same technique as in the Big Red Speedpaint - Finale