I like fighting ninjas or something similar.
And also big, dumb and slow enemys <img src="/ubbthreads/images/graemlins/smile.gif" alt="" /> especially if they can kill you in one hit (or almost anyway).
Maybe an idea would be a 4 legged (and 2 arms) scythe wielding demonlike char. It has a kinda slow attack but high movespeed. It has ramlike horns and it has the magic ability to put everything he touches with his scythe on fire.
So basicly a centaur from hell with some devillike looks (and a big bad scythe).
maybe give it some lobsterlike (or crablike I'm not sure) shielding and some nasty spikes on his shoulders. (And maybe also a tail with similar nasty spikes.)
I'd use red and black colors only (you know for the straight from hell kinda look). Maybe fire in his eyes, abit like sauron from lotr.
speaking of lotr, maybe balrog but in a smaller form, a winged flying demon is a must anyway.
and please add yeti's <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />