Restoring energy
Using your booster and special skills will drain your energy. If you run out of energy, remain idle and it will regenerate. You can also restore your energy by using items dropped from defeated enemies.
Various strategies
After progressing to the point where you are now having difficulty winning battles, return to previous stages to farm more coins, new robots and items. Although you will not earn gems by doing this, you will eventually farm enough items to allow you to resume your progress. You can also play in Endless Battle mode to get new equipment for your robot.
