The Sustainer was a large robot with artificial intelligence which served the Lezze-Eeserk species.
History and specifics[]
Sustainer was built to seek out a new homeworld for the Lezze-Eeserk and look after the surviving population in stasis aboard the world-ship Solopziz. It had access to advanced medical techniques that could repair and revive a dead humanoid. Because the Lezze-Eeserk had ravaged their home planet, during its travels the Sustainer sought a means of teaching them selflessness so they could avoid repeating history.
In 2274, it detected the Federation starship USS Enterprise and its probes noted the friendship between James T. Kirk and Spock. Through telepathy, the Sustainer created circumstances that forced Kirk and Spock to repeatedly sacrifice their lives for each other and for the Enterprise. It recorded their psyches during these experiences, then imbued that knowledge into the minds of the sleeping Lezze-Eeserk. (TOS comic: "A Thousand Deaths")