Ugly, 

missing limbs, 

extra limbs, 

blurry, 

poorly rendered faces, 

lowres, 

bad hands, 

text, 

error, 

cropped, 

jpeg artifacts, 

signature, 

disfigured, 

bad art, 

deformed, 

poorly drawn, 

close up, 

b&w, 

weird colors, 

watermark, 

deformed