During an enlightening drop-in tutorial with Phil about the design of my Shock Trooper, I was recommended towards images of muzzled dogs, stealth planes and overall angular designs. I also remembered the comments of my peers about the helmet looking like the head of the ancient Egyptian god Anubis, partially because of the upright ears. In these designs, I attempted to accentuate that feature and drag in some more references of Anubis. I also liked the idea of 'muzzling' the trooper because, like with all dogs wearing muzzles, the onlooker perceives the wearer of the muzzle as an inherently dangerous and vicious individual who has been tamed. This works well for the trooper as they are particularly brutal and vicious individuals who have been tamed and remain obedient to their master, Fat Cat.
Here are the images that were referenced to me as well as a few I looked up myself.