I Can Accumulate Proficiency, Starting from Alchemy - Chapter 709 - 319: Immortal Realm’s Void Prison, Burning Life Seed

... a macro perspective, the Daluo Immortal Realm is an incomparably vast world. Beneath this great world, there were originally thirty-six smaller lower realms, but a hundred thousand years ago, during the Yuan Gathering, a shocking battle ensued, causing the Daluo Immortal Realm to shatter, even breaking the barriers of the great world.

As for the thirty-six lower realms that relied on the great world for their existence, twenty of them were either shattered on the spot, occupied by the W ...