Hermes, the Guide of the Dead, is reputed to have written the "Emerald
Tablet of Hermes" in which he wrote about the "One Thing" which became
the first principal of alchemy. Cerberus was like a little puppy with
Hermes, thus at some point during the last decade before the End of
the First Age of Magic (966 GUE), at request of Glorian of the
Knowledge, he re-chained the Hound of Hell at the Tomb of the Twelve
Flatheads in the Dungeon of Zork.