loved how you did the skin texure and the spikes are amazing!!!
Sharprm> oh thanks for the edit ^^ and yes grey for the teeth could be better.
contrasts are ever my big problem, i'm too shy with it 
Manupix> owned ! :D i've been to speedy on the spikes .. i know i've completly fail on the shadows T_T mea culpa
good eye mister ;)
You could make it a bit more cohesive by cutting colors. eg. reuse grey to do outline for teeth.
The grey on the spikes could be made more pinkish to fit better.
Also could look at shading differently eg. http://www.mobygames.com/game/amiga/chaos-engine/screenshots/gameShotId,222633/
edit: edit: http://i39.photobucket.com/albums/e199/sharprm/sloppy.png
Quite frightening!
Maybe it looks a bit static? The teeth might have more volume too.
And I feel foolish saying this, considering color is your job, but I think the greys and pinks are disconnected, what about some purple or blue shade to link them?
Bienvenue sur PJ! ;)
He's got a really charming smile. :D