Thanks for playing and the feedback! The vast majority of the art I made by hand during the jam. The backgrounds, player, bosses, menus, fates animations, boss intros are all completely my own drawings. The harpy enemy I hand made using a free parrot animation for a template. The only assets I didn't create were the wolf and deer enemy sprites (which I altered quite a bit), the spinning stars, and the anger symbol in the player opening cutscene (edit: and the tornado from Cartoon Coffee's pack which I also changed a fair bit). Not sure what gave you that impression.
Glad to hear you liked some parts of the boss fight and thanks again for playing!