Steven Universe: Ghost Gem

Phantom Quartz were among the rarest and most intelligent of Homeworld's elites. handcrafted by White Diamond herself as her personal tacticians, advisors, and enforcers. Unlike other Quartz soldiers, they were not bred for brute strength but for superior strategy, logic, and precision.

Each Phantom Quartz was unique, regarded as a treasured creation, a near-perfect fusion of power and intellect.
But perfection is fragile.

During the Gem War, when Homeworld saw no other option but to unleash the planet-wide blast, it meant sacrificing both Crystal Gems and their own forces. In one cataclysmic moment, nearly every Gem on Earth was presumed wiped from existence, including White Diamond's precious Phantom Quartz.

But not all of them were lost.

One Phantom Quartz remained, poofed before the corruption wave hit, trapped in a bubble by Rose Quartz for reasons unknown. Left to drift in forgotten ruins for centuries, he only reawakened in the present day, emerging into a world where Homeworld had abandoned Earth, the war was long over, and his kind had become little more than a myth.