I enjoyed playing this game very much, though I didn't know you had to recharge your energy in order to continue smashing the knights, despite having read the instructions on this game's page :p

I thought there would be a Game Over screen, but was surprised when I found that any effort expended gives you a Victory message :D

A quick suggestion! You should give the player a reason to not hold down shift and charge, because at the moment you can just charge the whole time. Or maybe just get rid of charging entirely and just make it charge over time.