I just realized that I forgot to comment when I rated... SO
Oh, is it a bullet hell game. It is really intense, maybe a bit too quickly, but since it is an arcade style game, I cannot blame it for that.
The main mechanic is really creative and fun to play with. It wasn't obvious what the green enemies do, but I managed to figure it out after playing for a bit. (First I though they still attack me) (^^;)
It is certainly difficult, I only managed to see a/the boss once, and even that was while I was dead...
Overall, I really enjoyed the game, it's as fun as hectic, so you really did a great job! Amazing submission!