For those not in the know, Sudoku is the latest puzzle craze which sees the user with a grid of 81 squares. Some of the squares already have numbers in them, and it's up to you to figure out what goes in the blank ones. Gamers have to place the numbers 1 - 9 carefully as the puzzle is only complete when there are no double-ups of digits in the same column, row or 3x3 set. Sounds simple enough, and while the first two difficulty settings may be a breeze, you are sure to spend a good 30 - 60 minutes on some of the harder puzzles.

The game itself is controlled in a completely different manner to that seen in the Sudoku section of Brain Training, and in this case, that's a very bad thing. Instead of holding the DS like a book, you'll be holding it the traditional way, and instead of tapping a square, seeing it zoom to full screen so you can write the digits in, it simply highlights the square. Once the square is highlighted you select from a small keypad to the right which digit you think goes in. While it is only the default method, it can be changed to a written method, but frustration levels will rise when it fails to understand the number 5 thirty times in a row.

The default method isn't nearly as interactive as BT users are used to, but at least it works, unlike the number recognition. Once you have used a specific digit nine times the corresponding number on the keypad greys out, whether they are in the right place or not. The practice puzzles go a little easier on you and will show up as red if they are misplaced.

The top screen does nothing to help the presentation of the title. In fact, if it weren't for the fact that it tells you how long you have spent on the puzzle and what difficulty the puzzle is, there really would be no point to it. The top screen merely mirrors exactly what is going on on the bottom screen, which in essence means you can choose which version of the puzzle you want to look at; rather pointless, really.

Of the 400 puzzles, not all are selectable from the start, and this is where the game aspect of Sudoku Gridmaster comes in. Finish a puzzle within five minutes and receive four gold stars; within 10 and you'll receive three, and so on. When you have a certain amount of gold stars, more of the locked puzzles become available and soon enough you will have unlocked Sudoku rank tests. These tests are different to the standard puzzles in that they each have a time limit that you have to meet. With a good 20 minutes to attack the bronze test, only veterans will find themselves getting the platinum award.

A game like this needs to have its own dedicated website that allows users to download more and more puzzles. Even an online time attack mode would be great to see. But with this game offering only a little more than the added extra found in Brain Training it's hard to recommend this while it still has the retail price of a new title. Don't rule the game out completely, though, it may not look as fancy, or control as nicely but it is still a solid experience, just make sure you have the volume turned right down.