On the surface, Teenage Mutant Ninja Turtles II: Battle Nexus closely resembles last year's Teenage Mutant Ninja Turtles. It only takes a quick spin to notice the major differences between TMNT 1 and TMNT 2.
TMNT 1 featured a handy radar system which showed all the remaining enemies in an area on each level. TMNT 2 instead has directional proximity arrows. There's no radar system anymore, but if an enemy is off the screen to the right, you'll see a small bar to the right of the screen. Unfortunately, the radar showed you how *far* those enemies were you. It's not uncommon to be walking near the edge of the screen and get bopped in the nose unexpectedly. This is even more common in 2 player mode if you aren't standing directly next to your partner.
TMNT 2 also features some new jumping techniques. First, you have your regular jump. While in mid-jump, you can jump again and perform a double jump. So far, so good. But there's also the wall jump. Jump near a wall and hit jump again and you will push off and jump away from the wall. In the first level there are stairs next to a wall you have to jump up. Each jump is a double jump. Stand too close to the wall, and instead of jumping up the stairs, you will jump halfway up and then for some reason jump completely away from the stairs. It should not take a ninja turtle 10 attempts to climb a flight of stairs.
In TMNT 1, you had two main attacks -- a fast attack and a powerful attack. The problem was, they weren't much different. This has changed in TMNT 2. This time around, your power attack is significantly slower and much harder to land. That prevents you from just powering your way through the levels. I guess the best way to put it is they made the attacks more different, so the fast attack really is faster, and the powerful attack really is more powerful (and slower, and tougher to pull off).
The system in which you play is also different. At the beginning of the game, all 4 turtles are chosen. If you are playing by yourself, you will end up choosing all four turtles. Although only one turtle per player shows up on screen, the L1 (or was it L2?) button swaps between turtles. You will need to do this to accomplish things on the levels. For example, you will encounter force fields that can only be deactivated by one turtle, or objects that can only be used by another. If you play two player mode, you will each choose two turtles. If you choose 4 player mode, everybody gets their own turtle.
4 player mode? Yup, it's here! If you look up reviews for TMNT 1, that was the single biggest complaint about the game. This time around, they've included it. The other big complaint from TMNT 1 was that it was a simple button masher. This has been addressed too -- better AI, tougher opponents, and more interactive backgrounds make it tougher to simply punch your way through this one.
I almost forgot to mention -- all the cut scenes in this game are all animated cartoons.