Pay $PIXEL to fully refill the energy bar. The $PIXEL price will increase by 1 $PIXEL every time you refill and you can only refill the energy a fixed amount of times per day. For example you pay 1 PIXEL for the first refill then pay 2 PIXEL for the 2nd and so on then you can only refill your energy like 10 times per day so if you refill 10 times a day, you will spend a total of 55 $PIXEL per day for a total of 10,000 energy.