Category nine destruction rig
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A category nine destruction rig was a type of military vessel used by Wrechon Four. It was not only a ship, but a bomb as well, capable of destroying half a planet. Commander Kohrbal and Pheenan of the genocide squad travelled to Teymah to destroy the Ninexie, the Commander activating the self-destruct upon his death. Using telepathy, the Sixth Doctor was able to send Constance Clarke the access code, Gamma, Gamma, Three, Delta, Nine, and cancelled the destruct sequence. (AUDIO: Absolute Power)