Well, that was satisfying!
The aesthetic looked like a mixture of Hollow Knight and Ori, and it was working very well, because despite similarities, it actually managed to stay unique.
The sound design was on point.
At first I really didn't care for the dialogue, but halfway through the experience the whimsy made me care - I especially loved the tree ninja's dialog.
As a fan of cryptic secrets, I was quite pleased with the first thing required being to figure out a secret code to be played on a piano. After seeing the piano, I took a mental note that it exists and it payed off. On the flipside, I think a new player, especially someone not very familiar with games, could get lost and discouraged by the game starting this steep right away. Also, the piano looks like a one time gimmick, which rather shouldn't be used as an introduction to the game. For a good example of this, just look at the Skyrims first 10 minutes - this is a terrible intro.
What really holds the experience back for me is the combat - it's too simple, but maybe it's just your decission for the bigger version of this game, to turn even the combat scenarios into a moment to wonder about the story and ongoing puzzles. Either way, I like purposeful, challenging and fun combat, that's why I take away half a star.
Still, this is very promising, wishing you the best with this :)