Gomtuu
Gomtuu is a sentient, spaceborne organic creature, who also functioned as a space vessel. They lived for several millennia up through the 24th century, though its current whereabouts are unknown. It survived a near-extinction of its race, and to their knowledge, was the last of its kind. Gomtuu seems to have been born far from Federation space, most likely in another galaxy.
Upon its discovery by the United Federation of Planets and the Romulan Star Empire, it was dubbed "Tin Man" and the "Star Creature", respectively.
Viewed from the exterior, Gomtuu was a massive, dark-colored starship, shaped like a sunflower seed shell. The interior cavity consisted of a series of chambers and corridors, with gravity and atmosphere to support carbon-based lifeforms as a crew, with whom Gomtuu lived symbiotically. Its amorphous interior was also capable of growing furniture and equipment from its walls and floors.
It could project images from its exterior to the occupants, as another way of communication, as main communication was done telepathically.
Similar to a traditional starship, Gomtuu possessed what resembled a warp drive, had transporter capabilities, and was fully equipped to defend itself with a protective force field.
However, much of the technology was beyond the knowledge and understanding of Federation science. Its telepathy could reach over extremely large distances.
Gomtuu had been manned/occupied by a full crew, until an explosion in space generated radiation that penetrated Gomtuu's "hull" and killed everyone inside. Gomtuu wandered the galaxy for a millennia after the traumatic experience, vainly searching for more of its kind. Alone and without a purpose, believing itself to be the last of its kind, they eventually decided to commit suicide by orbiting a star about to supernova.
In 2366, "Tin Man", as members of Starfleet called him, was detected when a probe was sent to monitor the same star's supernova. However, also on a mission to monitor the star, Romulans discovered Gomtuu's existence as well, and a race was on to get to to the mysterious being first. As Gomtuu did not respond to traditional communication methods, the Federation sent a highly telepathic Betazoid, currently a guest on their ship, to make first contact.
The Betazoid warned Gomtuu of the Romulans' ill intentions, and the alien demonstrated its defensive capabilities. The shockwave destroyed the Romulan Warbird, and heavily damaged the USS Enterprise-D, though it was later revealed to be unintentional damage. Having deeply bonded through telepathy, Gomtuu and the Betazoid disappeared into parts unknown, seemingly providing each other with a new reason to live.
