This list of cheat codes and tips will show you how to unlock a new mode and secret weapons in Shin Megami Tensei: Persona 4 on PlayStation 2.
Unlockable Secret Weapons: By returning to completed dungeons, you can find the characters’ secret weapons. Note: No secret weapon available for Chie.
Unlockable weapon — How to unlock it.
* Kanji’s secret weapon: Defeat extra boss in Steamy Bath House.
* Kuma’s secret weapon: Defeat extra boss in Opera House.
* Main Character’s secret weapon: Defeat extra boss in Void Quest.
* Naoto’s secret weapon: Defeat extra boss in Secret Lab.
* Yousuke’s secret weapon: Find in boss’ den in Mysterious Shopping Street.
* Yukiko’s secret weapon: Defeat extra boss in Yukiko’s Castle.
New Game +: Finish the main game once to unlock New Game Plus.
Ultimate Weapons: Available only in a 2nd playthrough or more, Death will sometimes hide within treasure chests. Chests containing Death will prompt you to pick between the choices to open or ignore the chest. If you choose to open the chest, you will have to fight Death, which when defeated, will drop the ultimate weapons for the characters.