A river of words flowed between us.
Acererak was a powerful king who became a lich, and later a demilich. He appears in the original Tomb of Horrors adventure by Gary Gygax as the main adversary, and later as the guardian of the Copper Key, during the quest for Halliday's Egg.
Acererak first appears in the original Tomb of Horrors adventure (1978) by Gary Gygax as the main adversary. One of the areas in the Tomb is a "Chapel of Evil", described as "obviously some form of temple area - there are scenes of normal life painted on the walls, but the people have rotting flesh, skeletal hands, worms eating them, etc." He also has rubies for eyes, which he uses to steal the souls of his enemies.
The adventure described him as "a human magic-user/cleric of surpassing evil" who took the steps necessary to preserve his life force as the lich, Acererak." In Gygax's original tomb of horrors, Acererak was little more than a disembodied skull, who lurked in a crypt beyond a secret door in the back of the dungeon. To confuse adventurers seeking to plunder his treasure, Acererak had left false crypts scattered around the tomb, some of which were guarded by a false Acererak (which was really a zombie magically disguised as the lich). Therefore, it is possible that the lich that players confront on the egg hunt, is not really Acererak, but rather a decoy, repurposed by James Halliday to guard the Copper Key.
Acererak guards the Copper Key in a digital recreation of the Tomb of Horrors. If an OASIS avatar approaches him in the pillared throne room, they will be challenged to a match of Joust; should the player defeat Acererak in a best-of-three set, they will obtain the Copper Key. If the player loses, their avatar will be forced to fight Acererak. The rule to win the Copper Key is winning the match twice. Wade Watts was the first player to defeat Acererak, followed by Samantha Cook.