I love all the detail you are putting into the project. I tried to do a basketball-sized Death Star and just about went insane making all the panel lines...great job!
Just my 2 cents that may improve the sculpt...It appears your emphasis on the nose curving to his right is more than real life if you are going for the photo-matched likeness. Great work overall!
Holy cow, that came out awesome! Looking forward to the smaller skull as that will really tighten up the overall look. As Skeletor, did you refer to people as "you boob!" alot? I always loved that as a kid!!!
Smooth-On recommends...Ease Release 200
"IMPORTANT: If casting platinum silicone into Compat™ 45, only use Ease Release™ 200 when making your mold, DO NOT use Universal™ Mold Release."