Saving the best for last… Here's my rendition of Lovecrafts' Cthulhu; Mariners Blight Daemon Prince K'thul-hu!
After looking through tons of Photos of Cthulhu, I isolated 2 key areas to recreate; the giant octopus face and the rotten carrion like wings. The head came from Reaper Miniatures Eldritch Demon (read "Cthulhu") which for obvious reasons was a perfect fit and the wings were from a Vampire Counts Zombie Dragon for that added Nurgle feel.
I started with a base Nurgle Deamon prince. The Finecast version actually came in handier due to the fact that I had to chop and edit some areas. The thigh areas were re-sculpted to look like MKII & III armor as well as the shoulder pads. The larger shoulder pad was given a raised version of the Blight logo sculpted from green stuff and extra tubing was added around underneath the pads to enhance the look.
I added a tail from the WFB Manticore Model for that extra Daemon like element and a 3-eyed Kraken icon on the shin guard similar to the standard that is on the Terminators. Finally, like with the rest of the army, the base is from Secret Weapon Miniatures.
Here's some awesome reference pics of the "real" Cthulhu.