I'm not sure if people would like it, but I'm a fan of Quake, so I would welcome fantasy-style Quake monsters, especially Shambler (huge, furry monster casting lightning bolts) and Fiend (a fast daemon with claw-like hands).
Beside this Centaurs (half-human half-horse with bow) and Fauns (could confuse you with music, would drop a flute when killed) from Greek/Roman mythology.