Entering service to Sauron after being promised regency of the North, Agandaûr began amassing a vast army of Orcs, Goblins, Trolls, and Evil Men, while stirring up other dark forces such as the renegade Giant Bargrisar and the Spider Queen Saenathra.
Upon his master's command, Agandaûr gathered a host of Orcs and Goblins amidst the ruins of Fornost. The Witch-king of Angmar expected him to move against the North soon and Agandaûr assured him of this.
After returning to his seat of power in Fornost, the Orc-chieftain Tharzog reported the appearance of uninvited guests within the citadel. Outraged by his servant's incompetence, Agandaûr ordered him to call the guard as he made to leave. Pursued by Elladan, Elrohir, and their companions up the tower's rooftop, Agandaûr fled the scene on the back of his Fell Beast and summoned a storm to prevent the Great Eagle Beleram from trailing him.
Through the use of his agents and persuasion, Agandaûr was able to gain the allegiance of Bargrisar and Saenathra, while he personally negotiated and tried to forge an alliance with the Dragon Urgost. His allies defeated and his pact failed, Agandaûr resolved to assaulted Nordinbad, home to the Dwarves who had refused his offer of servitude to Sauron.
- The Lord of the Rings: War in the North Game