Press / in battle to slow the world's time to a crawl, allowing only Lightning to move normally.Description
Overclock (オーバークロック, Ōbakurokku?, lit. Overclocking) (also once identified as Lightspeed on the official page) is a battle element in Lightning Returns: Final Fantasy XIII where Lightning can slow time around her while she moves at normal speed.
When the player unleashes Overclock with /, time slows to 10% for everyone but Lightning, who attacks quicker and has quicker recovery. The ATB gauge is replaced by the Overclock gauge, which consists of 30,000 points and depletes by 1,000 points per second. When using an ability, the gauge depletes by an amount equal to the ATB cost x 160 points. When the gauge is nearly empty, Lightning can execute any ability regardless of cost. After the gauge is empty, the player resumes normal control of Lightning, and all three schemata will have their ATB fully refilled. Overclock has no effect on Battle Time.
Pressing / again while in Overclock unleashes Lightning's special attack, Army of One.
A track called "Overclock" appears in the game's original soundtrack as a fifteenth track on the third disc. It plays simultaneously with the currently played track whenever Lightning unleashes Overclock.
Behind the scenes
When making the announcement trailer of Final Fantasy XIII, a concept of the Overclock system was used in the battle system demo. In fact, no battle system had yet been designed for Final Fantasy XIII at this point, and the trailer was merely a visual demo for the feel of the game the developers wanted to portray. It appears, however, that the demo was the direct influence in developing the Overclock system for Lightning Returns: Final Fantasy XIII.
Overclocking is the process of making a computer or component operate faster than the clock frequency specified by the manufacturer by modifying system parameters (hence the name "overclocking").
Overclock shares its name with the Limit Break-esque system from Kingdom Hearts Re:coded.