One of my biggest difficulties is drawing the same person/character/critter and having it look like it's the same person/character/critter. So I doodled up the skeleton for these sheets (the grid and some fine-lined circles and lines for optimal cranial placement), and started working on them. Each one took about 2 hours to do, what with reference-hunting and corrections and all.

I contemplated making them more finished (light/shade, maybe inking/color) but decided to focus on one thing at a time.

Done in part at the behest of  out-of-the-boks