This is very fun, i like the gameplay and everything
I would only suggest adding levels and more ether like Hawklore said
and maybe harder enemies the higher levels you get, along with higher upgrades
4/5
serious issues with this game
the songs get off from the notes so it's hard to keep on beat
the songs are too long
and i hate how the music gets quiet when you miss a note, it throws me off
3/5
 "Level Up!"){kind=icon}
 "Take Something Literally"){kind=icon}
 "Battalion: Nemesis"){kind=icon}
 "Cell Warfare"){kind=icon}
 "Ether War"){kind=icon}
 "Synapsis"){kind=icon}
 "Super Crazy Guitar Maniac Deluxe 3"){kind=icon}
 "The Project"){kind=icon}
 "Fancy Pants Adventure: World 2"){kind=icon}
 "Icescape"){kind=icon}
 "wOne"){kind=icon}