Graphite studies from the imagination, based on Humaniod concept studies using various references from microscopic bugs to really ugly sealife creatures :)
I layed out a rough silhoutte with graphite powder (also gave me my mids), then loosely sketched out the design with a 2B. Using a 4B I then went and created the forms like muscles etc. Finally I used a 6B for deeper shadows. Then dropped in the highs with an electric rubber.
I hope they give you nightmares :P, ha!
-Enjoy! :D