The beautiful soundtrack along with the art style create a gloomy atmosphere that sucks you in. Such a thing is already difficult to find in high-budget commercial games, let alone a flash one, huge respect for that. I like the way thunder lights up the character's sprites and how you slowly sink deeper into the water when you stand still while swimming.
The controls feel good and the platforming is really smooth, and acquiring new skills helped keeping it fresh and gave me some reason to revisit places I had already been to. I've beat two bosses so far. Figuring out how to kill the first one felt quite satisfying, however the second boss is way too easy, even easier than the first.
I only experienced two problems. The frame rate drops quite often, most usually when I kill an enemy and it drops those little particles. I'm not sure if it's my computer's fault or what, but it is usually capable of handling some more graphic-heavy games, so it could be worth investigating. The other issue is that when I release the energy blast even the dead bodies do the hit effect. Are they supposed to do so?
There are some other things that may me design-related, but I'll point them out anyway. When I kill and enemy and get killed right after, my character's dead body still picks the experience particles up, which I thought to be a little weird. Also, how are the enemies able to completely dodge my bullets when I shoot them in the face? It felt somewhat dumb to have them completely forget about me the moment I jumped behind them.
You did a great job! Thanks for the amazing game.