A nice surprise for the fans of the older, beat 'em up Turtle games.
The graphics in TMNT are really good considering what the Gameboy Advance is capable of. The pixels on the screen are some of the best (only topped by Gunstar Super Heroes). Animations are slick and the enemies look just as good as the Turtles. What makes the graphic engine a lot better is that you can have a lot of enemies on the screen at once, just like the old Turtle games, and that was certainly a thumbs up for me.
The soundtrack to the game is surprisingly good. It's filled most with rock type riffs that can get pretty heavy. Because of this, you'll have some great music to listen to while you beat down a bunch of thugs. The sound effects, on the other hand, aren't exactly the best in the game, but they do get the job done. Just try not to get yourself distracted by the music.
TMNT, just like Teenage Mutant Ninja Turtles 2 and 4, is a side scrolling beat 'em up. All of the levels consist of going to the right, and then fighting a bunch of enemies at once on the screen. The number of enemies vary, but it's still fun as hell to beat them over the head with Raphael's Sai. Also, the enemy AI can be pretty decent, since the enemies can move around and get behind you while you're working on another group of enemies and break up your hot streak by punching you once. But even though something like that can happen, it doesn't take away from the fact that no matter which difficulty setting you put it on, TMNT is too easy of a game and it's way too short with very easy boss fights. It's also short, consisting of only 7 Levels.
Unlike Teenage Mutant Ninja Turtles 2 and 4, TMNT has more of an indepth battle system than those two. You can combo enemies by using a normal 4 hit combo, and the combos can rack up considering that you can be facing as many as 5 enemies at once. Getting higher combos will net you a higher score, and combos are easy to pull off. Alongside with normal attacking, you're able to kick your enemies that are behind you or in front of you across the screen and then continue beating up on the enemy you were focusing on. There are also a bunch of different move you can play with, including ones you can learn from the shops inbetween levels. You can also call upon one of your fellow turtles for help to help either attack your enemies or let them drop food when there are no enemies on the screen. The food they drop refills your health completely, so if you're in a tight bind, and are able to call upon your brother, then do so and refill your health. Also, once you reach a high enough Brotherhood level, you can use a Super Summon Move, which will completely wipe the screen of all enemies.
You can also attack and break objects that are in sight during the level. You can break down poles, break boxes and vases, and all sorts of things. This can be rewarding as well, since some of those items can drop items such as health pick ups or different weapons. Along with your normal arsenal of attacks, you can pick up stray weapons from enemies as they drop them, which in turn gives you more power for a short time, because stray weapons such as bats and poles will break after about 3 to 5 hits. I thought this was a good idea, since it would be too overpowering if you could keep a bat or Katana as your weapon throughout the entire level or game.
Inbetween levels, you can visit shops above ground to increase your stats or refill your health or gain extra lives and learn new skills. All of this costs money though. In order to get money, you can collect the coins the enemies drop, or you can complete mini games. Although there aren't that many mini games, you can find Splinter, April, and Casey inbetween levels and they'll give you certain challenges. Some of them are easy, like April's, whereas some of them are downright frustrating, such as Casey's and Splinter's. Alongside with the mini games, you can earn trophies after meeting a certain requirement. There are three types of trophies for you to collect for each category: Bronze, Silver, and Gold. This adds a little replay value to the game if you're looking to get everything.
The leveling system, while a nice idea, is a bit weak considering that you can only level up two times throughout the entire game, and each Turtle, regardless if you use him or not, will still earn experience points, so you can stick to one turtle if you want and not worry about anyone else.
All in all, TMNT is an excellent and surprising game which surely rivals both Teenage Mutant Ninja Turtles 2 and 4 as the best TMNT game ever. Older fans of the Turtles, as well as newer fans, will both enjoy this game a lot since everyone can find something about it they like, wether it's the nostalgic feel they'll get, or just the pure fun of beating around thugs like in the good old days.