In a massive feature article Japan's leading gaming publication,
Weekly Famitsuu takes a closer look at Square Enix's Final Fantasy
XIII for PlayStation 3. Famitsuu reports that at the time when
Square Enix showed off the infamous Final Fantasy VII technical
demo for PlayStation 3 at last year's Electronic Entertainment
Expo, Final Fantasy XIII was still in development for PlayStation
2. Thereafter, the development however decided to move the entire
project over to PlayStation 3.
While not much is known about Final Fantasy XIII's battle system at
this point, the article sheds at least some light on a few aspects:
At the bottom of the screen, next to the protagonist's HP, another
stat called ATB Cost is visible. This hints at a return of the good
old Active Time Battle (ATB) system, in one way or another.
Apparently every command executed by the player costs a certain
amount of those ATB Cost points. Next to the ATB cost stat, one can
make out the string "Lighting" . Famitsuu speculates that this is
in fact the protagonist's name. Furthermore, in the upper
right-hand corner of the battle screen, a circle-shaped gauge is
visible. Once the number inside this circle and other conditions
have been met, the protagonist can enter a so-called Overclock
status. This status has a slow-motion effect, effectively slowing
down everyone but the protagonist. However, making use of this
ability apparently brings some risk with it. The female
protagonist's weapon can be used as a gun or a sword. Depending on
opponent and situation, it will be possible to switch between those
two functions.
Source: RPGFan