Third TMNT game on NES, possibly the best.
Sound/Music: It all just simply rocks. There's even voice acting that isn't as teeth-grinding as most NES voice acting can be. All 4 of the turtles' famous catch phrases are used such as "Cowabunga!" and the music is wonderfully played throughout the entire game. Everything you'd expect, and more.
Difficulty: It's really not that hard at all until you get to the last couple of levels, just don't stop button mashing and you'll do fine.
Gameplay: Wow, where to begin. This has to be the best brawler on the NES aside from River City Ransom, hands down. You are able to play as any of the four turtles and play with a friend as well. Your mission is to go through the city, fighting off the Foot Clan and other minions while trying to reach the Technodrome and fight Shredder and Krang. Excellent gameplay, you'll keep coming back for more.
Controls: Pretty straight-forward, there are a couple of combos you can do but one of these takes one piece of your life away, yet it's the strongest attack you are offered.
Overall: All in all? This is better than the first two combined! I still have yet to go out and buy this sucker, it's so awesome I -need- it. No reason to not get this game at all.