The Battle for Andorhal was a three-way battle between the Forsaken, the Alliance, and the remaining Scourge forces in Andorhal.
With the Lich King defeated, the Alliance and Horde were able to claim separate portions of Andorhal and soon after began a crusade to claim the whole city, while the Scourge tried to keep their territory. Over the course of the battle both Koltira Deathweaver and Thassarian send adventurers to deal with the remaining Scourge forces. After defeating the Scourge leaders, the two death knight commanders enter a truce with one another; giving both the Horde and Alliance time to recover before they face one another. Some time afterwards, Alliance farmers, hungry from poverty, train in the art of combat and are equipped with armor by Alliance adventurers, so that they may defend themselves against the dangers of Andorhal as they farm food from Felstone Field. Once the battle has officially resumed, the farmers planned to aid the Alliance in retaking Andorhal by sneak attacking Koltira's forces from the rear. The farmers had Alliance adventurers take out Forsaken Outriders at the Writhing Haunt in preparation for their strategy. Shadow Priestess Vandis tasked Horde adventurers to kill Alliance forces hunting for food and the Alliance Laborers at Felstone Field in order to starve out their competition before the battle resumes. Lindsay Ravensun saw the Alliance farmers at Felstone Field as a nuisance to her desired new training grounds and planted false orders from Forsaken high command in order to plague Felstone Field; afterwards she used the Val'kyr to raise the dead farmers as new Forsaken recruits. The surviving Alliance farmers later form a militia and initiated their own sneak attack on Koltira's Forsaken forces without Thassarian's authorization. With his hand forced, Thassarian resumes the war with the Forsaken. After whittling each other's forces and killing some of the Alliance commanders in response to Alliance adventurers killing Forsaken commanders, Koltira sends agents of the Horde to speak with Lindsay Ravensun, whom he was told would be supporting him in the final battle.
During a battle in the city, the forces of the Horde and the Alliance fought united (while still fighting with each other) under a common goal to kill Chromie.
Upon meeting Ravensun, it is revealed that she is in reality Sylvanas Windrunner, who is aware of the truce between Koltira and Thassarian, and also their friendship which dated back to their service as death knights of the Scourge. Using the val'kyr, she resurrects slain Provincial Minutemen from the farmers' militia to recoup their casualties before sending agents of the Horde to eliminate Thassarian. Many of the recently created Forsaken Troopers and the Lesser Val'kyr — including the Val'kyr commander, Aradne — were slain by the Alliance adventurers. Despite their valiant efforts however, the Alliance were forced to retreat from Andorhal; as they were unable to stand against the Forsaken's overwhelming numbers and the onslaught provided by Sylvanas' Scourge-like tactics. As Horde forces enter the Alliance camp, all they find is the slain body of Lurid, Thassarian's skeletal minion, and discover that Thassarian and the remaining Alliance forces have retreated from Andorhal. With Andorhal now controlled by the Forsaken, Sylvanas called Koltira to her. After Sylvanas berated Koltira about his "weakness" and criticized Arthas' failure to remove such weakness, a portal appears and a chain drags Koltira into the Undercity. Sylvanas planned to eliminate Koltira's compassion for Thassarian and ensure his loyalty is to the Horde and more specifically the Forsaken.