Sorry about the confusion! that requirement is in the README file!
Great that its in the readme file... but using the itch.io client it opens the .exe. Chances are people might still not read the readme.
So you can make all the incredible art, but not warn people at the beginning in game that yes a controller is required? Sorry all you PC people with only a keyboard.
Ah, we had no idea the client opened the .exe directly. We added the warning to the page and download window as well. The issue is, the game requires multiple key inputs simultaneously at certain times, and most keyboards don't support that. That's why a controller is required.
In any case, we're currently looking into keyboard support!