Overall, I liked your game, however, it definitely needs some polish. For example:
● It would be nice to be able to move diagonally when pressing two buttons simultaneously (in battle). This would make movement feel less awkward.
● It's not always clear where to go, I think it would better if there were some sort of indication.
● I didn't like that you can only shoot horizontally - it really limits your movement.
● There is no fullscreen mode, and game window is not resizable. (Might be a problem specific to me)
Also, the game is too short, which is understandable, given time constraints.
Gameplay is fine, it serves its purpose, but (imo) it needs a bit more depth.
On the plus side, this game has some attention to details (like water shader, for example), which I really like. The transformation sequence is very cool, and so is your artwork in general.
I think, that more development time would be really beneficial to this game. Alas, we don't always have that luxury. So, in conclusion, I think this game is good, but it definitely has room for improvement.
P.S. Submitting your game 28 seconds before the deadline is something. Glad you managed to do it in time ;)