You'll have three weapons at your disposal, spread cannon, concentrated cannon, and your energy shield. The spread cannon will fire an arch of bullet out before you, while a concentrated will fire only directly before you. Your energy shield can be used to absorb incoming shot, however, your back and sides will remain vulnerable. The shield can also be used to damage enemies by ramming them with it. As you use it the shield will run out of energy and need to be recharged.