The Cryons were a crystalline humanoid race who were the native inhabitants of Telos.
Biology[]
From the Cyber-Documents, ArcHivist Hegelia observed that the Cryons were predominantly feminine in nature and were "not unaware of the delights of sexuality." (AUDIO: The Cyber Nomads) Cryons were pale and lean, with long fingers and fingernails, enlarged craniums and whitish skin. They moved slowly and had echoing voices. Due to their unusual composition, they could not survive temperatures above freezing and would steam and boil when subjected to heat. (TV: Attack of the Cybermen)
Technology[]
The Cryons had reasonably advanced technology, but they especially excelled in refrigeration technology. Their advanced refrigeration technology brought the Cybermen to Telos. They were also able to contact Earth from Telos and knew of the Time Lords. (TV: Attack of the Cybermen)
History[]
The Cryons built and lived peacefully in huge refrigerated cities until they came to the attention of the Cybermen. The Cybermen invaded Telos, took over the refrigeration and converted it into their cyber-tombs for suspended animation. They attempted to wipe out the Cryons, but some survived, unknown to the Telosian Cybermen. These contacted Lytton to hire him to hi-jack a time-ship that the Cybermen had taken control of. They kept a secret base under Cyber-Control, and worked to sabotage the Cybermen's hibernation units. They aided the Sixth Doctor in retrieving his TARDIS and destroying Control, but it is unclear whether or not they escaped in time and survived the subsequent explosion. (TV: Attack of the Cybermen) According to one account, they did survive, and with the Cybermen gone, they reclaimed Telos and began rebuilding their homeworld. (PROSE: Attack of the Cybermen)
The Sixth Doctor kept a Cryon pendant in his C chest. (AUDIO: The Carrionite Curse)
