The Eternal Ones are a race of god-like, extra-dimensional beings who consume all sentient life in the Star Control Universe.
They evolved from sentient organic beings until they lost their material bodies and became pure energy. They were afraid of evolution from physical to energy and tried to stop it, which required vast sentient energy. To harvest sentience in great quantity they planted "seeds" throughout the universe that created all the other races.
The Precursors became aware of this and devolved themselves to non-sentient animals and created semi-sentient machines called Daktaklakpak to re-evolve themselves when the harvest was over. The Daktaklakpak forgot their main objective and started to wander the galaxy collecting and protecting all Precursor technologies.