Orcs are a species of aggressive mammalian carnivores that band together in tribes and survive by hunting and raiding. Orcs believe that in order to survive they must expand their territory, and so they are constantly involved in wars against many enemies: Humans, Elves, Dwarves, goblins, and other orc tribes.
Orcs vary widely in appearance, as they frequently crossbreed with other species. In general, they resemble primitive humans with grey-green skin covered with coarse hair. Orcs have a slightly stooped posture, a low jutting forehead, and a snout instead of a nose, though comparisons between this facial feature and those of pigs are exaggerated and perhaps unfair. Orcs have well-developed canine teeth for eating meat and short pointed ears that resemble those of a wolf. Orcish snouts and ears have a slightly pink tinge. Their eyes are human, with a reddish tint that sometimes makes them appear to glow red when they reflect dim light sources in near darkness. This is actually part of their optical system, a pigment which gives them infravision. Male orcs are about 5½ to 6 feet tall. Females average 6 inches shorter than males. Orcs prefer to wear colors that most humans think unpleasant: blood red, rust red, mustard yellow, yellow green, moss green, greenish purple, and blackish brown. Their armor is unattractive besides -- dirty and often a bit rusty.
Orcs speak Orcish, a language derived from older Human and Elvish languages. There is no common standard of Orcish, so the language has many dialects which vary from tribe to tribe. Orcs have also learned to speak local common tongues, but are not comfortable with them. Some orcs have a limited vocabulary in goblin, hobgoblin, and ogre dialects.
Note: Orcs originally appeared in this form in the 2nd Edition Monstrous Manual for the AD&D game from TSR. Their use here is for the purposes of providing context for the campaign only.