Naruto: Ninja Council

On the Leaf Village Arena level, 1st Area (first level where you get the wind scroll) near the end of the level, you will fight a jounin-level enemy (big green ninja) and to the right of the platform he is standing on, there is a small crawl-way. Inside of the room, there is a large invisible scroll. When you acquire it, that character will permanatly learn level 4 Jutsus (if you save your game.)

Naruto
Red - Uses Kyuubi to heal himself.
Yellow - Uses Kyuubi to heal himself, then deals damage to all enemies on screen.

Sasuke
Red - Preforms an upward kick-aerial combo.
Yellow - More powerful version of the red combo.

Kakashi
Red - Preforms Chidori, hits all enemies on screen.
Yellow - More powerful version of red jutsu.

Use Naruto's Naruto Rendan (3rd special) in the red part (causing him to fail) against Kiba. Naruto will fart and cause Kiba to be paralyzed then Naruto will finish it up with Naruto Rendan.

Certain bosses are dealt extra damage when certain Jutsus are used on them.

Using Naruto's Harem no Jutsu on Ebisu will cause Ebisu to have a bloody nose and die instantly.

Using Kakashi's Dog Summoning no Jutsu on Zabuza will make all the dogs latch on to Zabuza, and Kakashi will preform Chidori on him, just like in the anime and manga.

Using Naruto's Harem no Jutsu on the 3th Hokage at the end of the final level will make give him a bloody nose also.