The Codex was a product of DarkStryder technology hidden inside an alien construct within the Kathol Rift. In appearance, it resembled a small pyramid with a metallic surface. It was delicate, with rough handling or falls damaging it, but remarkably light in weight. This weapon could locate and quantify the Force as well as enhance the Force-sensitivity of the user. It was sought by the Aing-Tii monks who saw it as sacred and therefore could not handle it by themselves. A loophole was found in training Makezh to navigate the Rift in order to bring the Codex to them, as he was immune to their religious beliefs.
After the Codex was retrieved it was brought to the Aing-Tii homeworld and placed into the Embrace. As a part of his five year journey to study the Force, Jacen Solo came into contact with the Codex when participating in the Embrace.
- Star Wars Galaxies: Trials of Obi-Wan (Mentioned only)
- "Waystation"—The Kathol Rift
- "Showdown"—The Kathol Rift
- Fate of the Jedi: Omen (First appearance)
- Star Wars Gamemaster Handbook
- The Kathol Rift
- Star Wars Galaxies: The Complete Guide: Prima Official Game Guide
- The Official Star Wars Fact File 75 (JED4, The Jedi)
- The Complete Star Wars Encyclopedia
- Jedi Academy Training Manual