Whenever battling, there are some things that you must keep in mind-
1. Stay focused! when a battle, online or not, you dont want to worry about
their rock bar, always keep your eyes on your notes.
2. Focus on battle gems! if there is a tough barrage of notes ahead of you and
you know you can't hit them all, make sure you at least hit the battle gems
they are your way to winning.
3. Store up attacks! attacks that are spaced apart(because battle gems notes
are spaced apart) are useless.
4. Attack so that they can't! Once you have stored up attacks, it is best to
use them when they have a chance to acquire an attack. Its easier to stay alive
when there isnt anything trying to make you miss notes.
5. Attack in succession! Once you have stored up attacks and attacked once,
keep attacking so that they can't recover
6(in the case of an online match). Keep a power-up steal on standby! if you
realize that the battle is going to result in sudden death, then you want a
powerup steal to get a death drain from them
Happy Battling!