Czernobog's Centaur

In American Gods, Czernobog rides an armored centaur with its face hidden by a metal helmet. Alex Jordan was so pleased with this centaur that he ordered several more; there were a few months in 1978 when he wanted to armor everything--even mermaids. If your Greek mythology is a little rusty, you can find an entry about centaurs in Bulfinch's Mythology (dreadful party guests).