While details of the battle system for Final Fantasy XIII haven't been officially revealed, speculation is beginning following the release of a new trailer on January 28, 2009. The trailer included the first footage of actual battle gameplay.

During E3 2008, members of the Square-Enix development team for Final Fantasy XIII sat down with reporters to discuss the game. While they didn't speak specifically about the battle system, Producer Yoshinori Kitase said he "took the best of X and XII and created something entirely new and evolved it... there will be monsters on the field but it's a little bit different from the MMO style that XII had."IGN: Final Fantasy XIII Preview

Fan Site FF-XIII.org describes the battle system as "revolutionary," and also says it will use a command system similar to previous Final Fantasy games, but use a fighting system similar to the system in Final Fantasy XII, where the enemies were clearly visible on the screen. In previous games, the player would encounter battles randomly and would be taken into a different screen to carry out the battle.FF-XIII.org: Final Fantasy XIII Battle System

• Eurogamer: FFXIII battle system revealed (April 7, 2009)

• Joystiq: Final Fantasy XIII's battle system explained (March 26, 2009)

• 1up.com: Final Fantasy XIII's Battle System Exposed (March 25, 2009)

• Ars Technica: Final Fantasy XIII battle system exposed, explored (January 29, 2009)

• MTV Multiplayer: Square Enix Releases Final Fantasy XIII Trailer With Gameplay (January 28, 2009)

• IGN: Final Fantasy XIII Preview (Battle System Info) (July 15, 2008)

• GameSpot: E3 2008: Final Fantasy XIII Roundtable Discussion (Battle System Info) (July 15, 2008)

• FF-XIII.org: Final Fantasy XIII Battle System

• Kotaku: Watch The New Final Fantasy XIII Trailer (January 28, 2009)

• Joystiq: Final Fantasy XIII countdown ends, new trailer released (Time: 2:49)