Variable tempo with the amazing Empress Effects ZOIA. I made a similar video with the Arturia Minibrute 2S (https://youtu.be/tnRIdncRrkY). I guess I've been a bit fixated with the idea after hearing Thom Yorke's magnificent song Dawn Chorus.
ZOIA is a wonderful device but either my programming sucks or the sequencer software is a bit buggy, because on the first round the main sequencer missed the step where it was supposed to jump into the second sequencer. That didn't happen on subsequent rounds. Whatever.