A Kirbtris on every level of Tetris Effect 

The 21-line ZONE clear was the work of Tetris mastermind Kirby703. After stunning the developers of the game with a 21-line Ultimatris, they renamed it after her. Then she scored a 22-line clear, and laid the groundwork for the theoretical (and ridiculous) maximum 23-line clear, and got that too!
My OUTDATED (!) guide: • MY ZONE GUIDE IS BROKEN?
Read a much better guide: docs.google.co...
And maybe check out Kirby's channel: / @kirby703