Malacath is the keeper of the Sworn Oath and the Bloody Curse. His sphere is the patronage of the spurned and ostracized. Boethiah created Malacath when he ate an Aedra named Trinimac. Malacath is the King of the Orcs and he loathes physical weakness. Most of the Daedric Princes don't recognize Malacath as a Daedric Prince and he is shunned by them, which suits his sphere.
In Oblivion, the player can visit Malacath's Shrine, which is swarming with orcs. Malacath's Quest is to free some enslaved Ogres from a nearby mine. Once all the ogres have been released you can return to Malacath's Shrine to receive your reward, Volendrung, an ancient hammer of great power.
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