Bruises

These are simply the result of broken blood vessels underneath the skin, a natural and spontaneous occurrence which should not be viewed as serious. However, they are unsightly and can be painful. See Pharmacopoeia for several alleviating substances, most notably the application of several leeches to the immediate area. The discoloration should quickly subside.
Note that in some cases, the bruises may actually swell or raise the surface of the skin. These are merely pools of blood; to eradicate the swelling, simply "squish" the blood around to the surround tissue and even out the surface. This is best accomplished with a standard kitchen rolling pin.