Albeit it doesn't have much to do with Pokemon, it still offers a great game!
For starters, the classic modes have returned untouched. Well, the only difference being the characters. There's a 1-on-1 wih the computer as you help Ash scale the Pokemon Puzzle League with difficulties that will REALLY put your skill to the absolute limit. There's a human 1-on-1 where you can test your skill against your friends, a practice mode, and even Prof. Oak who helps you learn the basics. But want to expand your knowledge? Let Tracy show you how in a VERY clever House that will broaden your skills. Also, take on Team Rocket in a Line Clear Challenge. To be honest, the Pokemon cast fits into these stories quite well.
The added twist that really gives this game its edge is this: 3D! Tha's right, now the grid changes from 2D to 3D. This changes the way you play as... well, now you've got more blocks to worry about. Think you're safe? Not when you find yourself in trouble because you forgot the blocks in the back! An interesting idea in the game that really works!
With other small things added, this game is very well done. It's got the classic Tetris Attack feel to it, but with Pikachu added in there. Still if you loved Tetris Attack, this game will definitely be a great one. If you haven't tried it yet, you should. If you get up to higher levels... you'll see some of the best AI I've ever seen in puzzle games!