Very cool game Idea and really good execution!
From a technical standpoint what you've made is really impressive, everything just works, and pretty well at that!
The only critic I have is the starting sequence, and the bosses AI.
The Starting sequence is pretty fast and I found it difficult to read everything in time (Though that may be since I'm not natively english).
The Boss got kinda stuck in the Trees, I think, so it was pretty easy to dodge him, just running around and flaming his toes.
The rest really is just polish, like the trees maybe having a particle explosion or something to indicate them being done, maybe more varying sounds and stuff like that, but other than that the game is pretty much as good as it can be, it's fun to play, it all works, it looks decent and it perfectly fit both limitations.
Great work, especially as a team of two!