A fun, charming, short RPG for all DS owners.
Story:
Not much here, sadly. Basically, an alien race known as the "Shroobs" take over Mushroom Kingdom in the past. Through an invention, Mario and Luigi notice how their kingdom has been destroyed. They team up with baby versions of themselves to destroy the kingdom and Princess Shroob, who has kidnapped Princess Peach. The writing in this game is not as strong as it was in the previous game, but it is still decent enough.
Gameplay:
Since you have four brothers to control, things had to be changed. One is that you can interact with the babies with your actions. The older Brothers no longer have the ability to hammer, as that has been passed on to their younger selves. And the hi-jump has been removed and replaced with a move that propels the babies from the backs of their older selves onto a high ledge. It's a little hard to explain but it works well.
In battle, things have changed a bit as well. Bros. Attacks no longer exist; they have been replaced with Bros. Items. Surprisingly, the change works very well. You can use a variety of items with two to four of the brothers, including green/red shells, and several flowers. There is a fair bit of button mashing involved here, but it isn't at all annoying in most battles. When the babies battle alone they also have access to the Bros. items, but not all of them because some require all four brothers. The regular attacks can also be enhanced when the babies are with their older selves, like a double jump or a super-powered hammer.
Graphics:
A nice improvement to the graphics from the first game, but they are of the same style, and some of the designs are a little ugly. But the graphics are never distracting, confusing or annoying at any point in time. Since the movements are fluid and the animations are strong, you'll probably like them. Also, I have never experienced any slowdown in game.
Sound:
Relatively strong music all around, except where it really counts - the main battle theme. It's not bad, but it's not as good as the theme from the first game. Might annoy you sometimes. The boss theme is a little better, but the best battle theme is unfortunately the final battle theme.
The voices for the babies and the older Bros are very strong, however. They talk a lot, and even though most of it is gibberish, it's funny gibberish. The sound of the babies crying is a little annoying, but it doesn't happen so often.
Other:
Since this is the second real RPG for the DS, you don't have that much to choose on this platform for an RPG. But nevertheless, this is still the best RPG for the platform, and a strong RPG in general. My only real complaint is that the game was very easy in general. I went back after I completed everything in the game except the final boss to level up, but I don't think I really needed to do that, as I actually died the least amount against the final boss. You don't need to really stop and level up at any point in the game, just attack all the enemies in your path, which to me, since I am not an RPG fan (first RPG I finished was this game), is great because I like getting on with the game instead of just leveling up. Looking through the GameFAQs, it seems that people had a hard time with the game. I don't see how, as this game is just easy all around the board.
Replay value:
Well, you can go back and play it again. There is one mini-game that you can go back and play as well, but it is not very entertaining and you'll play it in the actual game as much as you probably want to (once). Other than that, this game has zero replay value. Once you've finished, it's over. The game is pretty short as well. I finished it in 21:07, but I took the time to level up (it's pretty unnecessary) so it should take you around 14-16 hours. But even though it's short and easy, it's just a lot of fun.
Overall, this is a pretty good RPG for Mario and Co., and it should delight fans of the first game and newcomers alike (there is nary a reference to the first game).