Hey! Cool game.
A couple points of feedback:
Its really really difficult to find good situations to cast the beams in- usually standing still for so long kills me.
Its also pretty difficult to tell if im doing the beam inputs corrrectly or not. Well I suppose eventually you either get a beam or dont, but I think itd be nice if there was more immediate visual feedback on your ability to conform to the rhythm. Ditto for reloading (though reloading is closer- it does tell you pretty quickly that you got it wrong). In general im a bit confused about what 'on beat' means- quarter notes? whole notes? Itd be cool to have some pulsing UI element that showed you when the beat was on and off.