Neat puzzle!
I loved the sound when you finish the stage, but the wing flapping felt a bit too repeated and dull. The music was too low for me.
Visually, I enjoyed it, it's clear to see and thanks for adding the zone out button because it would be pretty frustrating without it.
For the game itself, I took longer than I'd like to admit to finish stage 4, 5 was easy after that. But at a point, when I finally managed to pass level 4, I pressed E and R at the last duckling, maybe there could be something else to restart a level, like another button a prompt to avoid such situations.
All in all, it was fun and challenging at the right level.