Illarion.org

He is venerated by orcs as the god of war and live sacrifices are made at altars drenched in blood.
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The rituals and ceremonies followers perform to bring war and more blood almost always involve sacrifice.
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Huge caves are lit with torches and fires, and ceremonial fights are held; it is a common belief that many disputes and quarrels are solved in these fights. Generally these fights remain ceremonial and do not end too bloodily but in some of the least civilised tribes the warriors still "slay each another in heaps".
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The wildest of tribes are still thought to perform sacrifices - rarely captives from other tribes and races, but more often volunteers from their own tribe who give themselves to the sacrificial dagger.
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Generally, animals are now slaughtered and sacrificed to the gods and ancestors before being consumed during the evening feast.
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In other races this feast has the more symbolic tradition of sacrificing a small animal, usually a chicken or rabbit, without many words.