Firing bullets will cost normal energy or special energy. Normal energy can recover gradually and special Energy can only recover by firing in specified mode or dodging. This is a STG game. Player need to switch back and forth in 7 modes to survive in the randomly generated enemies' attack. When normal energy runs out, TriangleWing can not move or fire bullets for 3 seconds, and when special energy runs out, TriangleWing can not switch for 3 seconds. ******. So it's fatal to run out of energy.
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