Final Fantasy, enormous, beautiful natural crystal suspended in middle of huge circular room, size of skyscraper, force field around suspend...

FFXV, distant future, alternate timeline. Insomnian Suspended, Sentient Crystal. The Crystal is imbued with an unknown living presence, speaking to that it chooses and making L'cie of those that accept its offer. Offering limitless power to a mortal, but with the price of a Focus and mission.