AMU needs some special fuel that contains energy cells floating around in space. Each cell gives some portion of power to move and to use guns. The more acceleration the protagonist has, the more energy is consumed by the Unit. In some stages of the game, when there are a minimum number of cells, it is important to be eco-friendly, saving some extra fuel by moving more slowly.
It is worth mentioning that the energy cells are extremely explosive; thus, many of them can be accidentally destroyed during a firefight. They can also be shot for the reason that if the cell is near an enemy, the intentional explosion may eliminate him.
When the Unit is out of energy, it stops; it cannot move in the automatic mode anymore. Now, the player has to use a manual starter to move the protagonist. On the screen, there appears a special virtual button that looks like a wagon wheel; the player may rotate it using his index finger. The rotation transforms into impulses of energy; the...