A religious artefact of the winged Skorr containing the recorded brain patterns of Alar, the teacher who turned their warrior race to peace, whose theft threatened a galactic holy war.
The Soul of the Skorr is the prize in the episode The Jihad. Two centuries earlier the Skorr were fierce conquerors until the teacher Alar civilised them. His brain patterns were preserved in a sculpture that became the centre of their faith.
When it is stolen, the ancient Vedala realise that the Skorr will launch a war of vengeance across the galaxy if their people learn of it. They assemble a team of specialists to recover it in secret: Kirk, Spock, the hunter Lara, the lock-picker Em/3/Green, the strong Sord and the Skorr prince Tchar.
The search takes them across a violently unstable planet. The thief proves to be Tchar himself, who wanted his people to be warriors again. He is overpowered and the artefact returned.