Ep 59. Musical Oppressors

Quellor sends his bats to fetch rope and a Giant Droolbeast to escape from the dungeon. The Understander places the six Crystals in the ceiling of M.A.V.O. HQ, and is baffled when nothing happens. The Understander realizes that a seventh receptacle exists in the center of the ceiling and that it must be for the Crystal in the Black Box.