Gomtuu

Gomtuu was a symbiotic, (possibly of cosmozoan species) lifeform/starship, discovered by both the UFP* and Romulan Star Empire* in 2366. Also known as "Tin Man" or "star creature", it made first contact with Betazoid Starfleet representative Tam Elbrun, at the Beta Stromgren system. Gomtuu was thousands of years old, and was lonely, after losing its original crew to a radioactive explosion. Emotionally scarred, it wandered for millenia, until stardate 43779.3. Elbrun, also having spent his life isolated and depressed, telepathically convinced Gomtuu not to choose suicide, as the Beta Stromgren red giant was going supernova. He was allowed to join it as a lone crewmember, thus completing one another's existance. The joined entity departs, never seen or heard from again.

(, Decipher CCG: Premiere)

Background

 * The Federation Vega Nine probe.
 * The Romulan D'deridex-class, under Commander Tallus.