This is an amazing game, so first I would like to go through all of the stuff I enjoyed the most!
I really commend the effort that was put into this, and the stability across platforms. Difficulty really ramps up across levels, but its really fun to play nonetheless! I can see that a lot of effort was put into enemy mechanics, graphics and the overall polish that is clear throughout the game, and it really shows!
Controls are also really smooth and fun to use, and I enjoyed using the powerups because they don't give you an unfair advantage over your enemies, they just keep it competitive enough to keep up with the new mutated enemies.
The music is really good, fits with the electronic theme and really gets you into the vibe of it, so awesome job on that too!
I would however suggest that to fit better with the theme, make it more visually like levels have a depth to them so it matches better with the "Under the Surface" theme as it isn't as evident when you first try the game. Even visually stacking the levels from top to bottom in a menu can help with this!
Note that this is really minor, as the new update you guys added makes it clearer exactly how it is beneath the surface
Overall though, this is definitely one of the best games in the jam, so really great job!!