Xtramos Crusade

The Xtramos Crusade was a xenocidal campaign of vengeance conducted by the Ironclad Templars Space Marine Chapter against the hated Drukhari that had attacked the Chapter's home world of Aevis during the First Defense of Aevis and severely damaged the Chapter's vaults, where most of their early history was lost. Now a fleet-based Chapter, the Ironclad Templars swore terrible oaths of vengeance and proceeded to launch an eternal crusade against their hated xenos foes, destroying any Drukhari they encountered.

Background
A year after the tragic events that occurred during the First Defense of Aevis, those Astartes that were ordered the escape from the vaults, managed to find their way to an Imperial Navy Ship which they then renamed The Eternal Flame. Once aboard the mighty ship, they would start the process of establishing the chapter. For the next couple of millennia, the chapter would become fleet-based. Those Astarte's that survived became the new chapter command and would embark on the chapters first crusade which the thought as a sense of honour to the failure of defending their home world. During the crusade, they'd assault small Drukhari outposts and fleets they'd come across, all while trying to find new recruits for the chapter and to some extent a new home world.