The holocron contained a prophecy that related to the Chosen One who would bring balance to the Force.
One prophecy referred to an evil "once dead" returning when the righteous lost the light. Many Jedi believed that the prophecy referred to the reincarnation of the Sith, whom the Jedi Order believed had been destroyed. Jedi Padawan Qui-Gon Jinn believed that the prophecy could refer to the Sith Darth Wrend, who was believed to have died but had returned once again to fight the Jedi. Eventually, the Sith were exposed to still be active with the discovery of Darth Maul, who killed Jinn in a lightsaber duel during the Invasion of Naboo in 32 BBY. At the same time, Dooku who over time was fuelled by righteous anger over corruption within the Galactic Republic fully embraced the dark side and joined the Sith as the new apprentice after slaying Jedi Master Yaddle.
Jinn believed that the prophecy of the female that was born in darkness would give birth to darkness referred to a Duchess of Malastare whose father waged vicious wars and gave birth to a daughter that became a Dark Jedi according to legend.
The holocron also contained a prophecy of kyber crystals which stated that when the kyber that is not kyber was revealed, then the time of prophecy would be at hand. On the mission to Pijal, Jinn and his Padawan Obi-Wan Kenobi found that Pijal's moon was a source of rare kohlen crystals, which jewel thief Pax Maripher explained were identical to kyber crystals on a macro level, and could only be told apart microscopically. The discovery of the "fool's kyber" led Jinn to believe that they were what the prophecy referred to, and led him to begin believing in the prophecies again.
The holocron of prophecy was old by the time Dooku joined the Jedi Order. Dooku became fascinated with the holocron, teaching his apprentices Rael Averross and Qui-Gon Jinn about it. Jinn later had his own Padawan, Obi-Wan Kenobi, study the holocron.
The holocron of prophecy first appeared in the 2019 novel Master & Apprentice.
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