Sega's tie-up campaign between Phantasy Star Portable 2 Infinity and Valkyria Chronicles 3 involves more than just a little sticker for your tank (there's that too, though -- see below).

If you boot up Valkyria Chronicles 3 when your PSP system has a Phantasy Star Portable 2 Infinity save file, you'll gain access in Valkyria 3 to PSP2i's newcomer character Nagisa as a guest character.

You'll also have access to a special mission called "Challenge From Little Wing Infinity." This mission involves an attack from the empire's elite forces on a strategic village. Your Nameless force will need to free the village. Defeat the enemy ace, and you'll take possession of Nagisa's Steel Hearts sword. Clear the mission, and you'll get a red ribbon as a bonus.

If you just want a Phantasy Star Portable 2 Infinity sticker to decorate your tanks, you won't even need a copy of the game. Simply input the following password in the EXTRA -> PASSWORD menu and you'll get a Rapiko tank sticker:

• R 7 2 Z P F 4 L 7 L 3 C 7 G 6 M