Tranell

 was a Torcaldian from Labeth who was used by Balthar as a conduit through which to drain other Torcaldians' time. Susan befriended Tranell when she visited Torcaldi with the First Doctor, Barbara and Ian. The Doctor allowed Tranell to drain some of his time to help repair the rift known as Torcaldi's Bane, allowing the Torcaldians to live a normal life. (PROSE: The Ruins of Time)