Definitely a worth playing game for all ages.
Pros:
(1) Nice little graphics and music.
(2) You wouldn't feel any stress playing this game. Each time you proceed on with the storyline, the fun increases.
(3) Easy controlling. You will not feel frustrated when killing enemys, climbing walls, moutains and etc. Everything is smooth, except when you're trying to jump onto some small stones from the water.
(4) A variety of ninjas that you can switch over during anytime in the game, except fighting bosses. Each ninjas have their own sets of unique skills and ability which makes the game even more fun, but, theres some setbacks on it, which i will explain in the "Cons" section.
(5) Cool actions. Don't get fooled by the "Cartoon-ish" design of the game. The action is solid, and killing enemy with your special attacks is always pleasing to see.
Cons:
(1) Way too easy for a game. Even with the difficulty set to the highest, it definitely is a breeze thru out the entire game. The reason why the game is easy because it is aiming for a wide range of players in the market, like i mention before, its targeting young children and working parents whom will mostly sit with their young children and play with them kind of game. Its a pity that the game is designed in such a way, if not, the entire game could be a blast.
(2) Since the game is so easy, many items and magic become extremely unneccesary. Items like the caltrops, pepper bomb, cherry bomb, time bomb, you will seldom, or should it said, never use it unless you wanna try it out for the first time. And magics like "Save point finder", Fireball, Tornado, Camoflage, is extremely unneccessary, considered that it causes a high lot of Ki energy and isn't really that effective at all.
(3) Non engaging variety of ninjas. Yes, it is good to have more than 1 ninja to switch in between battles, and having their own sets of unique attacks, but, it somehow isn't enough. 90% of the game doesn't require you to switch in between ninjas at all, since your main character Hiro, is strong enough to take out all kinds of enemys. Some ninjas like Tora (The tiger ninja), Suzume(The female ninja with the flute), is extremely unneccessary in the game. Tora's only unique ability is to sprint in a very fast speed, but you have to spend a special point to JUST sprint, which I believe no one will use the precious special point JUST to sprint, and to consider that the map isn't THAT big, why would you want to sprint so fast? As for Suzume, her ONLY unique ability is to mesmerize the enemy around her, again, consuming a special point just to mesmerize the enemy around her, and to consider that its casting time is long.
(4) Collecting item isn't neccessary at all. Theres a item call the Jizo Statue, and whats the point of collecting it? I mean look, so what if you have collect all the items thru out the game? There isn't any reward or any kind of achievement. I was hoping for the game to unlock some kind of special character, or at the very least, unlock some special scene or something, but no, even if you collect 100% of all the items in the game, there isn't any achievement or reward.
So, below is what i think that would make the game so much more fun, and to consider that the game isn't targeting its player for kids, i bet this game can reach a 9/10.
(1) Make each and every ninjas that you can control a very different feeling, and make it such a way that using each of them will have their own equal sets of pros and cons. Take Tora for example, his normal movement speed can be made in such a way that it is faster than any ninjas that you can controlled. The game mentioned that Tora is wild, quick, and stealthy, plus, his using a claw-like weapon like a wolverine, thus his normal attack and special attacks could be remake in such a way that it behaves like a wolverine. There is so much cool ideas that can be implemented for each and every unique ninjas that you can control. These goes for Suzume, Futo(The fat ninja), Kunoichi(The female spear ninja, but i love her special attack very much). As for Shun(The archer ninja), i find that he is unique enough to be on-par with the main character, and each and every ninjas should be what Shun is like, to be on-par when comparing it with everyone.
(2) Increase in the game difficulty regarding on the tactical,stealthy, and even better, implement a combo system, a stealth system or whatever system that will do the game good. For the combo system, firstly, it is definitely pleasing to see numbers of combo flying, secondly, more combos will earn you more points or whatever. For stealth system, you get to chose to fight with all the enemy, or to be sneaky and sneak thru them. With the stealth system implemented, sneaking thru a large number of enemy will gain you rewarding points too, other than to miss out your precious experience points and making stealth a no-go for everyone, and this is what the current game is like. As for the tactical part, make it in such a way that using items like caltrops, shurikens, bombs and etc is rewarding and effective. The game could be re-design in such a way that, for example, enemy is standing below a tree, and the tree got bee-hive on it, using Shuriken, you can knock down the bee-hive and thus, enemy is chased by the bee and so on. This is just an example, and just by thinking all kinds of events and ways to use the item if the game were to be re-design, there will be thousands of ways to play this game.
Bottomline, even though the game is easy and designed for a wide range of players, it is still enjoyable and worth playing.