Koei has announced Nobunaga's Ambition: Tenshouki for PlayStation Portable. The company's fourth title for Sony Computer Entertainment's handheld is already the fourth version of the game, which had previously seen releases on the PC platform, PlayStation One and Sega Saturn. Compared to previous versions, the PlayStation Portable release will feature an improved interface, a re-done arrangement of visuals and movie sequences and faster processing times. The three key words for the game are education, battle and army corps. 214 castles across Japan are waiting to be conquered by your armies. Up to eight armies can be created and the control of the land is handed to army leaders from within your clan.

Nobunaga's Ambition: Tenshouki for PlayStation Portable will be available in Japan on August 25th for 4,800 yen ($44.09 US).

• Official Nobunaga's Ambition: Tenshouki Website