Wow, I started playing this not realizing you had made an ENTIRE metroidvania, hats off my man. The music was all great and the second (mine) area reminded me of The Dig, kinda. In a good way.
The only thing I would bother changing so far is the drone controls--they're a little touchy. Especially when I just want to move a little bit. (Though I was playing on mouse and keyboard, so that might be a me thing?)
I'll probably go finish this some time, but for now I gotta leave a comment and rating. Really great job!