Millennians

The Milennians are an alien species featured in the film Godzilla 2000. Their solar-powered spaceship crashed on Earth during the Cretaceous period, and they remained dormant for ages until drilling operations exposed them to sunlight again, waking the sunken menace. They initially plan to modify Earth's atmosphere to suit their needs, but as they're attacked by Godzilla, they decide to instead modify themselves using genetic material from the monster, hoping to acquire its regenerative abilities. The ship's crew manifests itself as a huge tentacle creature somewhat resembling a mixture of jellyfish and mushroom; but whether they were originally a single being or not is never clarified. Using genetic samples from Godzilla, the gestalt creature modifies its own genetic structure, giving rise to the hybrid monster known as Orga. It battles Godzilla and attempts to consume more tissue from him to further transform itself into a clone of the monster, but Godzilla fires a radiation blast inside Orga's mouth, obliterating the alien.