Naruto Shippuden: Shinobi Retsuden 2 Cheats (DS)

Complete the indicated task during gameplay to unlock the corresponding character.

Unlock Uchiha Itachi: Complete Sidequest 1 - Instead of going South in Story mode to find
Sai, go East to do the sidequest. 

Unlock Hoshigaki Kisame: Complete Sidequest 1 - see Uchiha Itachi 

Unlock Deidara: Complete Sidequest 2 - Instead of going South in Story mode to find Sai go
East and then North-West to find Shino who will give you sidequest 2. 

Unlock True Form Sasori: Complete Sidequest 2 - see Deidara  

Unlock Kabuto: Win 15 battles in Survival mode. 

Unlock Legendary Sannin: Win 15 battles in Survival mode.

Unlock One Tail Kyuubi Naruto;

Complete Story mode on the difficult setting.

Unlock Non-Shippuden Characters: Win 15 battles in Survival mode on the difficult setting.

When you beat Story mode the Exploration mode option will become an available feature.