Just before they were to take part in the [[Battle of Gathalamor]], [[Fleet Primus]]' High Command became unable to make contact with the [[Shrine World]]. Rather than risk the entire Fleet in a possible ambush, a small recon force{{Fn|1b}} led by [[Shield-Captain]] Achallor was sent by [[Custodian Tribune|Tribune]] [[Colquan]] to determine the Battle's status.{{Fn|1a}}  However Achallor and his Shield-Host soon became swept up in the battle and deployed in an attempt to stop a [[Chaos]] superweapon from devastating Fleet Primus. At the climax of the battle for the weapon, known as the Bone Cannon, Achallor and his Brothers came into battle with [[Dark Apostle]] [[Kar-Gatharr]] and his [[Word Bearers]]. Summoning the powers of Chaos, the Dark Apostle was able to transform himself into a hulking monstrosity. Achallor was slain by Gatharr, though the Dark Apostle was struck down by [[Imelda Veritas]] and her [[Sisters of Battle]] shortly after.{{Fn|1c}}