"Heraldic Beasts" are those chimerical critters that are not found in nature. Yales, gryphons, bagwyns, and cockatrices are only a few of the more than fifty imaginary animals encountered in heraldry. These are usually blazoned in all their technicolour glory, ie: a cockatrice displayed gules, winged and crined vert, beaked, taloned and armed or.

"Ordinary Beasts", those that occur in nature-- lions, boars, deer, and giraffes, etc., as well as all manner of birds, fish, and insects-- are either blazoned "proper", meaning that they are painted as they appear in nature, or given a specific colour, ie: the "Red Lion" (a lion rampant gules) that occurs on the Royal Flag in Scotland.

While most crests (beasts or otherwise) are depicted on a torse of the livery colours of the armiger, hats and coronets are exempt from this rule. "Critters" are another sometime exemption when encountered on seals and signet rings, although they should properly be depicted on a torse.