Centaurs have the lower body of a horse and the upper body of man. Centaurs are known as wild, untamed and brutale. Hence 'Cento' in the name which means 'to goad' or 'to wound'.
A recent mention of Centaurs acting as such, can be found in Fablehaven: Grip of the Shadow Plague (book three). There are Centaurs in many stories and for the most part, are actually written as they are meant to be. The Chronicles of Narnia also have Centaurs. They are battle ready but also angry.
Let's just say, I never want to get on a Centaurs bad side.