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Battles in FFXIII take place on the spot and depending on the command being used, the viewpoint will change automatically in order to present a battle that is fast and smooth. If there are other members in the party, they will help you out with moves such as follow-up attacks on enemies that you just sent flying away. You can also switch to other characters on the fly during battles.

In the image above, Lightning is up against a large size "Heavy Attack Manasvin" made by the Holy Government. The machine is being used for patrol as well and the massive looking laser attack seems deadly. Its various parts suggest a wide variety of attacking options.

Command Stock: Players select the "Action" (the five buttons near the bottom left of the screen) they would like to use, which is then moved to the Command Stock slots (three slots above the Action buttons) to be executed in turn. Some "Action" buttons seem to have several layers behind them, which means you'll have more than five actions to choose from.

Command Cost: Each of the "Action" has a number attached to them, this is the "Cost" or the number of slots that particular "Action" will take in the Command Stock. For example, you can have three Fire command in the list since it's "Cost" is only 1 but you can only use Firaga, which costs 3, if you have three empty slots in the Command Stock.

Enhanced ATB (Active Time Battle): The bar underneath Lightning's name (the one with 444 value) indicates that the game will be using ATB system, where players can perform various actions before it's empty. However, ATB in FFXIII is a little different and can be controlled by the players as it is affected by the kind of commands being executed in the Command Stock. Commands with larger "Cost" will drain the bar faster compare commands with lower "Cost".

Symbol Encounter: Enemies are visible on the map and again there will be no battle screen transition.

Chain & Bonus: Located at the top right of the screen, Chain shows the number of consecutive hits you inflicted on the enemies while Bonus' use is still unclear at this point. Previous reports shows "Overclock" in place of Bonus, Famitsu says this probably has something to do with increasing certain ability of your character. The word "Break" can be seen replacing "Chain" in some screens, still no official words on that but Famitsu says it probably related to Final Fantasy VII's Limit Break.

Enemy's HP: Unlike previous games, enemies' name and HP are displayed.

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quote Cruxis Mana

ATB stands for Active Time Battle.

Yes, it means the game is turn based.