Many years ago, there were three races that ruled the land. Humans, pillars, and gems. The humans and the gems flourished in the sun, as pillars languished in the dark. One pillar, Kars, sought to conquer the sun. You know the rest.
Kars made the stone masks, they didn't work, and he exterminated the rest of his kind except for three others, two of whom were babies at the time.
He realized that the gems held the secret to overcoming the sunlight. Specifically, a gem called Aja. Kars realized that if he could carve out a part of Aja's body, he'd have the final piece to his plan. It had to be perfect though, one wrong move and he'd have an imperfect stone left.
Of course, he tried to kidnap Aja on multiple occasions with the help of Esidisi.
It never worked, and Kars and his followers were forced to sleep for a very long time.
The year is 1889. The day: February 7th. Jonathan Joestar has just drawn his last breath. Dio Brando will later sink to the bottom of the ocean with Jonathan's body. Erina Joestar has escaped the sinking ship and is holding the baby she rescued. A boat will pick her and the baby girl up soon.
Deep underground, something stirred.
This is the start of our story.