Hey hey ~
I dug your game a lot! The mechanics were super solid, the visuals were enjoyable and the music was a nice touch. I'm really impressed at how clean the game looks given the timeframe it was made in.
When I was fighting the last boss I wasn't really sure if I was doing any damage or how close I was to the end. I think that I hit the 3-gem sequence like 3/4 times and wasn't sure if I was making any progress because it didn't move past it without another key input. I also noticed at one point that two of the keys ended up being the same color which made me lose some health.
All the UI was clean and made sense, and I think that your gameplay was super creative. I had a lot of fun playing this, great job!