The Battle of Skalathrax was the final campaign the World Eaters Traitor Legion fought as a unified Space Marine Legion against their hated rivals the Emperor's Children Legion on the Daemon World of Skalathrax located deep within the Eye of Terror. Due to the actions of the former World Eaters Captain Khârn the Betrayer, the XII Legion all but consumed itself in a bitter internecine conflict that saw it fractured into countless smaller warbands. The World Eaters Legion would not reunite again except briefly for the First War for Armageddon in the 41st Millennium.