Githellion Ath'ulwei is a Dire Avenger Exarch of Craftworld Alaitoc who, before his current position, was an Outcast because he found the rigid strictures of Eldar society too claustrophobic. During this time he wondered the Webway for decades, but all the while he felt the ravenous hunger of Slaanesh clawing at his soul and grew to loathe the Chaos Gods and their servants, with an unbridled hatred. However destiny finally found Githellion, after he intervened in a pitched battle between an Eldar colony and a mob of Ork raiders and saw the fury and perfection of a Dire Avengers squadron. Watching them in battle made Githellion feel like the touch of the Phoenix Lord Asurmen was guiding him and he fully devoted himself the Dire Avenger Aspect Temple. Over the many centuries that followed, he became an immaculate embodiment of his Aspect, treading so far down the Path of the Warrior that Githellion can never return to what he was.
Currently, Githellion is leading Alaitoc's forces, alongside other Craftworlds, in the conflict that has enveloped the Imperium worlds in the Antian Sector. Though he has a history of aiding the Imperium against their common foes, Githellion can not be counted to aid them in this conflict; as the Eldar have their own mysterious plans for the embattled Antian Sector.