This Tedryn Holocron manifested as a radiant cube, easily held within the hand. Its composition consisted of a milky jade crystal block adorned with ancient writings across its polished exterior. Functioning as an interactive repository of wisdom, this Jedi educational tool seamlessly integrated ancient organic crystalline structures with technological components. The metallic elements featured intricate patterns suggestive of considerable age.

The internal crystals possessed the capacity to discern the alignment of a Force-user with the light side, although any individual with Force abilities could activate the holocron via contact with the design on its side. Upon activation, the holocron projected a rudimentary green-tinged hologram representing its primary gatekeeper.

Access to the knowledge stored within the holocron was available to all, albeit to varying degrees. At its most basic, the holocron functioned as a mere recording device, a compilation of records accompanied by interactive holograms of their creators. This fundamental knowledge could be accessed directly, akin to consulting a computer encyclopedia, or by interacting with the current gatekeeper.

Nevertheless, the most profound insights remained accessible solely to a Jedi. The inner organic crystals served as the gateway to deeper levels of understanding. Even a Dark Lord of the Sith—such as Darth Sidious, who possessed the device for three decades—lacked the capacity to unlock its restricted information. Advanced teachings and narratives were conveyed directly by the Masters who contributed them to the holocron.

The Tedryn Holocron was specifically crafted to assist Jedi Masters in unraveling the mysteries of the Force. Even individuals already trained in the ways of the Jedi could derive significant benefit from such a learning resource.

The gatekeeper, represented by a Jedi Master's holographic simulation, functioned as an integrated search and retrieval mechanism within each holocron. The fact that a specific gatekeeper presented certain information did not necessarily imply that they were the original recorder of that information, as all gatekeepers could access the data contained within the holocron.

Initially, the holocron bore the name of Tedryn, but it later became commonly known as simply the Jedi Holocron, or the Holocron of Bodo Baas. To prevent confusion between Vodo-Siosk Baas and Bodo Baas, and also to honor their predecessor, the New Jedi Order referred to it as the Tedryn Holocron. Tedryn may have been the originator and initial gatekeeper of the holocron. Before the onset of the Great Sith War, Jedi Master Odan-Urr, an early gatekeeper, added a record detailing the Great Hyperspace War.

Eventually, the Tedryn Holocron came into the possession of Vodo-Siosk Baas, a Krevaaki Jedi Master and Jedi historian. In 3997 BBY, his holographic representation introduced Exar Kun to the recent history of the Sith, including Naga Sadow and Freedon Nadd. Vodo's hologram acquainted Exar Kun, Ulic Qel-Droma, and the Great Sith War to the students of Luke Skywalker more than four thousand years after his passing. Subsequently, Luke inquired of Baas regarding the fate of Exar Kun, and the gatekeeper revealed that Kun had slain his own master, Vodo himself, when the latter attempted to redeem his apprentice from the dark side. Vodo-Siosk Baas was the last gatekeeper to be invoked, as the spirit of Kun destroyed the holocron before Baas could disclose Exar's fate to Skywalker.

An additional gatekeeper recounted tales of intrigue within the Galactic Republic to Skywalker's apprentices, while another gatekeeper shared the story of how the young Yoda became a Jedi with Luke.

Bodo Baas, a descendant of Vodo-Siosk Baas, served as the final gatekeeper of the Holocron. His hologram presented a partial account of Ulic-Qel Droma, a concise depiction of the dark side, and the prophecy penned by Baas' master. Later, Baas suggested that ancient Jedi artifacts might be discovered on Ossus, a venerable Jedi training center, and that survivors of the Great Jedi Purge could be located there. Subsequently, within the Jedi Praxeum, Luke requested that Baas elucidate the power known as Alter Mind to Corran Horn in the apprentice's chamber.

According to Obi-Wan Kenobi, the Tedryn Holocron harbored millennia-old secrets and some of the most closely guarded Jedi history and teachings. It encompassed information pertaining to the origins of the Jedi and the Sith, as well as their earliest conflicts.

Vodo-Siosk Baas created a recording about the conflict known as the Hundred-Year Darkness, in which he talked about the Second Great Schism, how the Dark Jedi manipulated the dark side to transform animals into warriors, mounts, and Leviathans, and the final confrontation on Corbos. By the time of the recording, the Jedi Order had discerned that the exiled Dark Jedi had subjugated the Sith species on Korriban and that Ajunta Pall had established an Empire.

Sometime after 5,000 BBY, Master Odan-Urr consulted Jori Daragon, Anavus Svag, and the Dark Holocron regarding the Great Hyperspace War before creating a record to preserve the complete narrative of the war for the Jedi Order. In the record, he spoke of hyperspace explorers Gav and Jori Daragon of the Koros system encountering the descendants of the Exiles, who had become Dark Lords of the Sith Empire. Odan-Urr recounted Naga Sadow's launch of an assault employing illusions to deter Republic forces. Following the Sith's defeat, Odan-Urr retrieved the Dark Holocron from a ship and learned of Sadow's escape.

At some point before the Great Sith War, when he was around a thousand years old, Ood Bnar documented his prophecies within the holocron. The device also contained information about Ood Bnar himself, the Neti species, and the planet Ryyk.

Vodo-Siosk Baas's hologram discussed the battles of Empress Teta and Deneba.

Arca Jeth created a record concerning the Freedon Nadd Uprising, in which he discussed Freedon Nadd and his successors, King Ommin and Queen Amanoa, as well as Jeth's students: Tott Doneeta, Ulic, and Cay Qel-Droma. Jeth noted that Nadd had lent his support to the founders of the Krath: Satal and Aleema Keto.

According to Bodo Baas, three Jedi Knights attempted to conquer the dark side by delving into its secrets, but all three met their demise. Vodo-Siosk Baas made a record regarding the Great Sith War, instigated by Exar Kun and Ulic Qel-Droma. Bodo Baas retold the saga of Ulic Qel-Droma to Leia Organa Solo, albeit with certain discrepancies for reasons unknown.

• Bodo Baas on the Second Sith War: Mandalorian Wars, Rakata, Korriban, Revan, Malak, Star Forge, Bastila Shan, Sion, Kreia, Nihilus, Brianna, Atris, Visas Marr, Ruin [2]

• Bodo Baas on Darth Ruin [2]

c. 1010 BBY Jedi Master Pernicar on Wud Mortull, the New Sith Wars, and the Sith lightsaber

580 BBY Bodo Baas on the Zeison Sha

580 BBY Bodo Baas on the Matukai

before 796 BBY Rekpa De's numerous statements on lightsaber duels

• 3996 BBY , Tolaris Shim on Ulic and the four stages of the dark side [2]

• 3951 BBY , Deesra Luur Jada on the reformation of Revan and on Dantooine [2]

• Bodo Baas on the dark side [12]

• Luke discovered clues within the Holocron that led him to believe that some Jedi had survived Vader's program of extermination. [18]

• The Holocron revealed to Luke that the planet Ossus in the Adega system had served as a center of Jedi learning for thousands of years. [18]

• Stories of the young Yoda becoming a Jedi. [3]

• Bodo Baas discussed the three aspects of the Force and the power of Alter Mind. [16]

• Stories of Old Republic intrigues. [16]

• Prophecy of Bodo Baas's Master concerning the Skywalker twins and the resurrected Emperor Palpatine. [2]

• Bodo Baas on training a Jedi [2]

• Odan-Urr on the Force Sever power [2]

• Bodo Baas on the Second Sith War: Mandalorian Wars, Rakata, Korriban, Revan, Malak, Star Forge, Bastila Shan, Sion, Kreia, Nihilus, Brianna, Atris, Visas Marr, Ruin [2]

• Bodo Baas on Darth Ruin [2]

• Odan-Urr on patience [2]

• Odan-Urr on how a Jedi must behave in public [2]

• Rekpa De's numerous statements on lightsaber duels [2]

• 3996 BBY , Tolaris Shim on Ulic and the four stages of the dark side [2]

• 3951 BBY , Deesra Luur Jada on the reformation of Revan and on Dantooine [2]

The Holocron's origin dates back to a period preceding the Great Sith War, possibly attributable to Jedi Master Tedryn, after whom the artifact received its name. Tedryn may have been the original gatekeeper of the holocron, succeeded by a lineage of Jedi who contributed to its contents. Master Odan-Urr, an early gatekeeper, incorporated a record pertaining to the Great Hyperspace War. Another gatekeeper was Ood Bnar, who was around a thousand years old at the time and recorded his prophecies within the Holocron.

By 3997 BBY, Vodo-Siosk Baas had acquired possession of the Holocron, becoming a gatekeeper by imbuing it with his knowledge and memories. On one occasion, he discovered his apprentice, Exar Kun, questioning the holocron about the Dark Jedi Freedon Nadd and the Sith. Baas deactivated the device, believing that such knowledge was intended solely for Jedi Masters.

Around 600 BBY, Bodo Baas inherited the Holocron and reorganized all of its recordings. By 590 BBY, he utilized rudimentary hologram technology to add records of Jedi teachings and history, compiled by a group of Jedi in the Adega system.

The Holocron was presumed to have vanished sometime before 290 BBY, but it was in the possession of Ashka Boda.

In 19 BBY, at the onset of the Great Jedi Purge, agents of Emperor Palpatine brought Jedi Masters before him to be interrogated and tortured for long-forgotten secrets and remedies that could aid him in his pursuit of immortality. The Tedryn Holocron was among the possessions of Bodo Baas, who was executed by the Emperor. Shortly afterward, the device came into the possession of Master Ashka Boda. The Dark Lord executed Boda as well and seized the Tedryn Holocron. Palpatine exploited the secrets within the holocron to evade death through the dark side and cloning technology, documenting some of the holocron's secrets in his Book of Anger. However, the majority of the ancient knowledge remained inaccessible to the Dark Lord, as it could only be accessed by Jedi Knights. He regarded the Holocron as merely a collection of ancient records. The resurrected Emperor kept the artifact in his study within the Imperial Citadel on Byss.

Later, Obi-Wan Kenobi described the Holocron to his apprentice, Luke Skywalker. Kenobi believed that the holocron could facilitate the reestablishment of the Jedi Order.

In 10 ABY, Leia Organa Solo was captured by the resurrected Emperor on his throneworld, Byss. The Sith Lord presented the Tedryn Holocron to the Jedi, attempting unsuccessfully to sway her to the dark side. Leia managed to escape with the holocron. Aboard the Millennium Falcon, she listened to Bodo Baas's rendition of Ulic Qel-Droma's downfall, pondering whether there was hope for Luke or whether he had delved too deeply into the dark side in his endeavor to conquer it from within.

Following the battle of Mon Calamari, Leia returned to Pinnacle Base, where she once again accessed the holocron. She inquired of Master Baas about her brother's future, but the gatekeeper responded that he could not discern it due to the obscurity surrounding Skywalker's fate. He then recounted a prophecy penned by his own Master. Moments later, a fleet of Star Destroyers led by the Eclipse emerged from hyperspace above the Pinnacle Moon. The resurrected Emperor demanded that Leia and the Tedryn Holocron be delivered to him, offering to discuss a truce if the Rebels complied. Leia accepted his terms but left the holocron in her chambers. Aboard the Eclipse, she realized that Sidious's control over Luke had become too potent and that the dark side was consuming him. The siblings engaged in a duel until Leia managed to break Sidious's spell over Luke, and they confronted the Dark Lord together, fulfilling Bodo Baas's ancient prophecy.

Subsequently, Luke discovered clues within the Tedryn Holocron indicating the potential survival of Jedi from the Purge. He dedicated numerous standard weeks to searching for Jedi, eventually locating Dark Jedi Kam Solusar on the Space City of Nespis VIII. Meanwhile, Leia spent extended periods with the Tedryn Holocron while Luke was away. During one such session, Baas informed her that Vima-Da-Boda could assist them.

Luke learned from the Holocron that ancient Jedi artifacts were possibly situated on Ossus. His new ally, Kam Solusar, was initially unimpressed with the small cube, but he was taken aback when it sensed him and activated. The image of Baas imparted cryptic wisdom and instructed Kam and his fellow Jedi to exercise patience. Skywalker and Solusar journeyed to Ossus, where they encountered Ood Bnar, a hibernating Jedi Master from Exar Kun's era, whose prophecies were stored within the Holocron. With the assistance of the native Ysanna, the Jedi discovered a Jedi library that had remained undisturbed for four millennia.

By 11 ABY, the Tedryn Holocron was housed in a small library, where Luke Skywalker's apprentices could study it. Skywalker convened his twelve students in the grand audience chamber of the Massassi temple on Yavin 4 for a formal inauguration of the Jedi Praxeum. He invoked gatekeeper Vodo-Siosk Baas to impart a lesson to his apprentices. The ancient Krevaaki Jedi Master spoke of the Great Sith War, as well as Exar Kun and Ulic-Qel Droma, cautioning the students against the temptations of conquest.

Tionne Solusar studied Jedi history from the holocron in the month following her arrival at the Praxeum, transcribing its data to tapes and holograms with a sense of urgency. Her studies enabled her to assist the other students with historical examples when Master Skywalker's instructions were not sufficiently clear. After Gantoris constructed a lightsaber, Corran Horn suspected that he had learned how from the Tedryn Holocron, but Luke explained that an inbuilt restriction mechanism prevented users from accessing knowledge for which they were not prepared.

Following the death of Gantoris, Horn advised Master Skywalker to reiterate the historical lessons of the Holocron to the students to instill a sense of history and purpose, thereby reducing their vulnerability to the corruption of the dark side. Bodo Baas recounted the heroic exploits of ancient Jedi Knights and their battles against the dark side to the Jedi hopefuls.

Corran Horn attempted to gather information regarding the murder of Gantoris, and Baas explained that, at the height of the Sith Wars, Yavin 4 had served as the seat of Sith Lord Exar Kun. Kun enslaved the Massassi and compelled them to construct temples in the jungle, as Naga Sadow had done previously. Eventually, the Dark Lord was slain in a Jedi attack. An auxiliary gatekeeper shared stories of court intrigue within the Old Republic with the students, without specifying the subjects of his tales.

After Corran Horn and Tionne had accessed all the information pertaining to Exar Kun, Luke attempted to access the deeper levels of the device. However, when he inquired of the Vodo-Siosk Baas gatekeeper about Exar Kun's fate, the spirit of the Dark Lord, who had been imprisoned on Yavin 4 since his death four millennia earlier, interrupted Vodo-Siosk Baas by destroying the Holocron.

Transcripts and copied data collected by Tionne Solusar and stored in the new Jedi library on Ossus preserved the teachings of the Tedryn Holocron after its destruction.

The Tedryn Holocron was initially mentioned in the endnotes for Dark Empire 2, authored by Tom Veitch and published on February 18, 1992. It was referred to as an "ancient object" from which Palpatine learned Essence Transfer, with no further details provided. It was subsequently mentioned again in the endnotes for Dark Empire 4, published on June 23,1992, and appeared in Dark Empire 5, published on August 18, 1992, and in Dark Empire 6, published on October 20, 1992. Throughout Dark Empire and the Dark Empire endnotes, the Tedryn Holocron was referred to as "the Jedi Holocron". This designation was also used in Dark Empire II, the Jedi Academy Trilogy, and Firestorm. The opening crawls for Tales of the Jedi 1, Tales of the Jedi 3, and Tales of the Jedi: The Freedon Nadd Uprising 1 referred to "the Jedi Holocron", which was implied to be the Tedryn Holocron due to the absence of other known holocrons at the time of their publication. However, Tales of the Jedi: Dark Lords of the Sith referred to the Tedryn Holocron as "a holocron" and also mentioned a Sith holocron, which later appeared in Tales of the Jedi: Dark Lords of the Sith 4. The name "Tedryn Holocron" was first used in Tales of the Jedi: The Sith War 1 and subsequently in Jedi vs. Sith: The Essential Guide to the Force.

In The Essential Guide to Characters, the holocron featured in Dark Empire was described as distinct from the one in Dark Apprentice, a statement that contradicts the text of Dark Apprentice and is therefore considered an error.