- For the episode about these items, see Golden Disks of Knowledge (episode)
The Golden Disks of Knowledge are a collection of disks, made of solid gold, containing valuable and highly sensitive information. Ages ago, the wisest men and women of the universe came to Eternia to store their knowledge in the disks. The Council of the Wise appointed Zanthor as the keeper of the disks, to prevent them from falling into the wrong hands.
However, Zanthor was tempted into surrendering the disks to Skeletor, who promised him great power in exchange for his treachery. The knowledge Skeletor gained from the disks greatly enhanced his power, and allowed him to build Snake Mountain. The Sorceress considered the threat Skeletor poses to Eternia a direct result of Zanthor's crime. Having gleaned the information in the disks, Skeletor buried them away in a deep cavern beneath Snake Mountain, guarded by the terrible serpent for whom he named his fortress.
The Council of the Wise sentenced him to an eternity in the Phantom Dimension, whereby he would exist in Eternia as only an immaterial ghost unable to be seen, heard, or felt. After a time Zanthor came to accept the Council's punishment as just, and regretted his crime. In his phantom form, he was easily able to breach Snake Mountain's defenses to locate the Golden Disks, though he lacked the substance to abscond with them. Zanthor eventually sought an audience with the Council to be freed from the Phantom Dimension long enough to atone for his crime by retrieving the disks. Zodac, the only remaining member of the Council, agreed to this proposal, but Zanthor soon discovered that what he thought were the disks were in fact forgeries created by Skeletor to prevent their recapture. Frustrated, Zanthor and He-Man nevertheless continued to search Snake Mountain until the real disks were recovered, whereupon they were returned to Zodac for safe keeping.
The Overlords of the Eternal Dimension decided that henceforth Zodac himself would guard the Golden Disks of Knowledge, and Zodac named Zanthor as his assistant in keeping watch over the universe.