Thank you so much everyone!! It’s tremendously encouraging to seeing these characters so well received! I apologize for not being able to get back to all of you at the moment. I hope to answer more questions and emails as soon as time frees up a little on my end.
Mahlikus The Black /Maudeeb: Glad to hear you recognized the music and that is has the same effect it has for me 
Tyrone70: Eiad pretty much nailed it. It’s just based on trial and error. Sometimes I break a blendshape into multiple inbetween shapes, to get more radial motion (i.e the open jaw shape consists out of 4 shapes). That way I have a little bit more control over the blendshapes and am able to keep the underlaying skull in mind.
KonginChains: Regarding the blendshape / key driven displacement maps. It’s all blendshapes, no bones. The eyeballs have eyeconstrains to a couple locators though and a very subtle bit of skinweights are applied to the eyelid area, to give it a bit more fleshy feeling. I exported displacement maps for many of the faceshapes. Each of these maps are hooked up in the shading network.
With a Plus Minus average node (set to subtract), the shader calculates the difference between the base displacement map and the expression displacement map(s).
The amount this calculation result map gets dialed in is controled by a Multiply Divide node, where I simply link the Input2 x value to my blendshape through a set driven key.
If you want to know more, pick up a copy of hyperreal creature creation, a book part of the autodesk series, co-written by Jeff Unay. Or the book Stop Staring by Jason Osipa. Both these books cover the process of key driven animated displacement maps in a very clear understandable manner.
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