Thank you for your feedbacks, could you explain a bit more why you think the limitation isn't really utilized effectively ? ^^
Viewing post in Crystal Beats jam comments
I hadn't a lot of time to make a good tutorial, each enemy type (Rubis, Citrine, etc) has an instrument and a rythm playing on top of the music, that's why they pulse in a rythm.
If you shoot them in rythm, you inflict them damage, if you don't match the rythm you won't do any damages.
You can succeed by spamming the shoot but most of your shots will do nothing, I also disabled the penalty when it's a wrong shot (not in rythm) otherwise casual players would have a too much hard time.