Sotek

Sotek, at one time called Khoteth, was a student of the Vulcan mind-lord Zakal. However, he later joined Surak's movement of peace sweeping Vulcan. However he had made a promise to Zakal to preserve his Katra, so when his former master was dieing he returned to place Zakal's katra in a vrekatra. About two-thousand years later when Zakal's katra was released, Sotek had a final duel with his formal master on board a Romulan Bird-of-Prey in the body of Dr. Keridwen Llewellyn. Sotek died then when the bird-of-prey self-destructed.