Pretty nice looking games boys.
But there are some things that you need to have in mind:
The first is that once you start a jump you can't cancel it, so if you start casting a jump but then you realize that you already have enought momentum you already waste a battery.
The second one is that if you waste some batteries at the beginning you can end without enought batteries to follow or go back ever if you rewind.
So if you add a way to rewind more you can have a work even nicer.