I'll give this one a try. May not be able to compete, but eh, tough life.
For some reason I started with their steeds. I tried to make them show the traits of each horseman, hence War's horse has a buff helmet, making him resemble either a bull or a dragon [by engravings and the wing-leg guards], both brutal creatures. Conquest's horse is vain [conquerors may or may not become vain having subdued others], and I had the idea of a viking longboat, since they were uhm... maneuverable and vikings used to be all over the place. To further enhance this, I gave the horse masks on its side, hanging from the saddle, similar to how vikings would hang their shields outside the boat. Or that's what the media wants us to believe.
I honestly don't like Famine's steed, so it's subject to change.