[Source] The Holocron of Belia Darzu was a Sith holocron created by Belia Darzu, a Dark Lord of the Sith who reigned during the last quarter of the New Sith Wars. A four-sided pyramidal device, the holocron contained Lord Darzu's knowledge of the dark side, particularly Sith alchemy and the techniques used to create her technobeast army. Following Darzu's assassination, the holocron remained inside her stronghold on the planet Tython, serving as the final vestige of her power. Centuries later, the holocron of Belia Darzu was recovered by Darth Bane, a Sith Lord who sought the secrets to constructing such a device of his own.