Congrats on completing a game. It is a large project and you and your collaborators should feel proud.
Some few things
Consider looking at existing color palettes, the colors are to bright. Especially the background and ground color, they are not that important for the game (no platformer element and no intractability with it). If you go with pixel art, then lean into it, also include the background.
The last final boss felt a little hmm. simple. I noticed he had new moves, but I could just move close and press attack repeatedly and got nowhere close to dying. Maybe the damage the enemy deals should be way higher, but they should warn much more to the player and the attacks should be parryable/dodgeable.
Those are my initial thoughts, but keep up the good work and home to see you next year :D