This game is great, and I will go over the parts of why it's great. It provides a unique movement system, which opens up a lot of puzzle opportunities. It provides a good flow of momentum, which can influence speedrunning or just having fun. This can be shown in the level that introduces the balls because I was able to drop down to the spikes and it allowed a quicker way to end the level. The graphics are detailed, but also simplistic, which allows for less eye strain, and being able to focus on the gameplay itself. Finally, the sound design is really great, and the gimmicks, aka the moving walls, falling spikes, and balls, which would give the game a 5/5. Another well make game from mmatt_ugh.
Edit: I speedran it, and got a time of 2 minutes and 37 seconds. Really fun game!