Guardians of the Galaxy director, James Gunn, has revealed that he had only recently become aware of Marvel's use of the Celestials in Eternals, despite including the species in both Guardians films. First appearing in Marvel's eponymous Eternals comic run in the 1970s, the Celestials are a centuries-old, extra-terrestrial species within the Marvel universe that are responsible for the creation of the entire galaxy.
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