Note: This game is also titled Naruto Shippuden: Ryujinki.
Successfully complete Story mode. Then, play Story mode on the Hard difficulty, and the alternate costume will be available.
Successfully complete Story mode on the Easy difficulty to unlock Wind Style Dragon Rasengan.
After getting the "Shadow Clone Scroll 2", summon the Shadow Clones, and use a Charged Rasengan. It will be a Wind Style Rasengan.
Summon a Shadow Clone, then use the Charged Rasengan. Instead of being a Normal Rasengan, it will be a Giant Rasengan.