Bat-winged Sharks! Run!

Cue "The Flight of the Valkyries."

A Snail Riding a Flying Platypus

Phorbas of Argos, Armored Satyr

The idea here was that the creatures of Greek myth stuck around and were simply incorporated into the societies which developed in the Mediterranean after the fall of Rome. I placed this guy roughly in the period of the early Crusades, which gave me some liberty to mix and match periods of armor. He's a mercenary with a collection of pieces picked up along his journeys. 

When it came to the animal anatomy, the biggest challenge was getting the right mechanic without making him look dainty and unstable. He's supposed to be a warrior, after all. For that, I looked at the chunky hoofs of Clydesdales and beefed up the leg muscles accordingly.  

Alien!

 

I referenced various of bugs and creepy-crawlies to design an alien that would wig me out if I were the one trapped alone with it on a spaceship. I also had fun with custom brushes and grungy textures for the worn industrial interior.

Armored Snout Badger

I set out to design a fictional but mechanically-plausible digger, so I mashed up features from some of the world's best dirt-movers: the mole, pangolin, anteater, and badger.