I enjoyed the frantic tile-dragging action - it took about half the board for me to understand what was going on, but it ended up being pretty enjoyable.
The colors of the tiles changing once combined into a big enough group took a few plays to get used to - due to the frantic nature of the gameplay, I found myself using those colors for pattern recognition, and when they changed color it somewhat threw me off my flow.
The achievement system was a pleasant surprise and made me play a few times in a row to get more of them.
The only issue I noticed is that you have a small typo in the intro "unit" instead of "unite", but thats quite minor overall. The gameplay is solid and I couldn't find a way to break anything. The clicky/snappy sound effects made everything feel really nice and have tactile feedback to what I was doing. I also think you did a really good job implementing the jam's theme. Thanks!