I thoroughly enjoyed this one, well done! Here's some of what I liked the most:
- Great low-poly art style
- Brilliant choices for music for each level. They always managed to be calming but either simultaneously ominous or eerie - which I thought was cool
- The water effects on the waterfall in level 3 were very nice
- The general idea behind the game was very unique for the given theme
There were a couple of very minor things I think might have helped:
- Capturing the mouse input in the window. I went full screen and was sometimes dragging my cursor off onto my 2nd monitor and right clicking there
- Some smoothing/linear interpolation on the panning would give a nicer experience moving about
In summary, great work!