In the treasury of the Lost Tower of the Celestial Knights is a covered crystal ball. When uncovered it glows a dazzling green before showing the spectator the plight of those that the tower is terrorizing. The spectator is able to communicate to the victims through the crystal ball by talking to them. If the victims overcome their fear then they are conjured into the treasury to join the crystal ball's spectator, with any metamorphoses that the tower inflicted undone.
In the original script the crystal ball was guarded by a marilith.