One of the best anime fighters up to now.
Hero's History - which covers the four main arcs of the Naruto anime, the Genin Training arc, the Leaf Destruction arc, the Tsunade Search arc and the Sasuke Retrieval arc.
Ultimate Contest - in this mode you enter in a contest where you have to get a certain number of cristals, in the first phase. In the second you must collect as many cristals as you can, to advance to the final, where you will fight against a final character. In this mode you can complete various missions, with different difficulties, learn new jutsu, costumise your characters's jutsu and train them.
Naruto UN 3 has 42 characters, from the most known: Sasuke, Naruto, Rock Lee, Kakashi, to new people: Kimimaro, The Yellow Flash, the Sound Four and many more.
This game as some nice combat scheme, but it's kind of simple, with few combos, the music is kind of poor, it has many, many, many,... collectibles, from videos, to figurines, to images.
One of the new things in this game, are the special transformations, such as the cursed seal or the kyubbi, the giant battles, with transformatios such as Manda, Giant Chouji or Inner Sakura.
Basically, i think this game has some features that make it worthwhile.