A noble exemplar of the Grey Knights Space Marine Chapter, Castellan Garran Crow is both head and Brotherhood Champion of the Purifier order. Crowe is charged with the wardenship of the powerful artefact known as the Blade of Antwyr, an evil sword that continuously brings him both physical and spiritual peril - forever tempting him with promises of power or binding his will with its blackest sorceries.
Both head and Brotherhood Champion of the Purifier order, Castellan Garran Crowe is considered a flawless soul, immune to the temptations of Chaos. Garran carries a burden greater than any of his Battle-Brothers, for he is charged with the wardenship of the Black Blade of Antwyr. This infamous artefact was first encountered during the latter years of M37, during the mad years of the Occlusiad, unearthed amongst the ancient ruins of a temple by the apostles of the Blind King. This Daemon weapon of prodigious power swiftly corrupted its discoverer's mind and body. Together, sword and slave made bloody war upon the Vidar, Tremayne and Darkspire sectors, a war only ended by the intercession of all 8 Brotherhoods of the Grey Knights. The blade and its wielder both vanished into the Warp in the aftermath. Three thousand years later, the foul blade reappeared in the material universe upon the doomed moon of Tethyrs, crossing paths with the Grey Knights once more. On this occasion, the blade's bearer was finally slain, and the custodianship of the foul artefact fell to the capable hands of the Grey Knights.
Unable to destroy the Blade of Antwyr, the Warp-spawned weapon was impervious to all means at the the Chapter's disposal. Reluctant to cast the evil sword into the void of interstellar space the Grey Knights knew that eventually a new bearer would be drawn to its evil aura. To seal it away in a vault within their Fortress-Monastery would be to invite corruption of the chamber's guardians. A fateful decision was made to place the Black Blade of Antwyr into the safest prison the Grey Knights could conceive; that of the wardenship of the Purifiers order. The Purifiers in turn placed the blade into the incorruptible hands of their Brotherhood Champion. For 1,000 years, the blade has been passed down from one incorruptible warrior to another, until finally reaching the hands of Garran Crowe.
The wardenship of the Blade of Antwyr constantly brings Castellan Crowe both physical and spiritual peril. When not beset by insane mortals and desperate Daemons drawn to the sword's evil, Crowe must constantly do psychic battle with the blade itself, stemming its constant sibilant whispered temptations with his iron will. For the blade strives to tempt the guardian with promises of power or bind his will with the blackest sorceries. The Castellan must forever remain on guard, for the sword constantly offers to lend its strength to his own in the pursuit of victory. Though many bearers would embrace such an offer, counting on their strength of will to control the sword without becoming corrupted themselves, Crowe has never succumbed to these temptations no matter how dark the hour or desperate the battle. Garran Crowe has remained incorruptible and inviolable, remaining so until the day of his eventual death.
- Codex: Grey Knights (5th Edition), p. 42