The Pureblood Knights are the order Mohg, Lord of Blood, has been founding for the dynasty he has not yet inaugurated. Their oath is administered by Varré, the Tarnished's first companion at the Roundtable, and the trial is recorded in the two Lord of Blood's Favor descriptions. First the white cloth : 'Pure white oath-cloth given by Varré. The final trial to be anointed a Knight of Mohg, Lord of Blood. "Soak the cloth with a maiden's blood... The blood of anyone's maiden will do. You are maidenless, after all."' Then, after the cloth is soaked : 'Fully reddened oath-cloth, dyed in a maiden's blood. The final trial is complete. Luminary Mohg is sure to welcome you into his service, as a knight who will lay the foundations for his dynasty.'

What dynasty Mohg means is the canon's slow joke. The Pureblood Knight's Medal flavour text states it almost wryly : 'Proof that one is a glorious knight of the new Dynasty of Mohgwyn that the Lord of Blood will inaugurate. For Mohg yet slumbers beside the Divinity. Be patient. The new dynasty is nigh.' The Divinity is Miquella, abducted in his cocoon. The Knights are sworn to a king who is not yet ascended, attending a court that is not yet opened, in a dynasty whose first generation has not yet been born, and they have, by the time of the Tarnished's arrival, mostly murdered each other in invasions through the Three Fingers' instruction. The Pureblood Knight is, in the strictest measure, a knight of an absence.