Polarium is broken down into two main sectors: a puzzle mode and a challenge mode. The puzzle mode gives you the chance to churn through 100 increasingly difficult puzzles. A puzzle is made up of black and white squares - normally in some kind of pattern - and by drawing a line over squares they will flip over, reversing the colour. To defeat a puzzle one must create horizontal lines of the same colour to make a line disappear, and with one continuous stroke from the stylus clear the entire puzzle. The training takes you through everything you need to know, from how to deselect something already selected, how to backtrack your current stroke through to using the extra space around the outside of the puzzle to your advantage. The difficulty of these puzzles gets - for the most part - progressively higher, but it isn't unusual to come across a puzzle that you spend 20 minutes trying to figure out only to find the next one you can breeze through in seconds.

A nice added feature is that the top screen can be used to show your last attempt. It allows you to know where you went wrong, and if you have the hints turned on it can - after 5 to 10 minutes - show you where a good starting place is. The trick is not to only focus making the puzzle all one colour but to focus on the puzzle one line at a time; it isn't uncommon to sit there for 20 minutes only to have someone else going through the same puzzle in a quarter of the time. It really is a brain game.

One of the best things about Puzzle Mode is the ability to create and save to cartridge puzzles you have made yourself. Once you have created the puzzle it asks for you to complete it - so it knows that it can be completed - and converts it into an extensive, numerical password so that any friend can enter and have a go at your puzzle. It's this option that really helps keep Polarium in your DS that bit longer.

Challenge Mode should have been where all the fun was at, and the first couple of attempts may be quite fun, but once you get past the first round it seems to get stagnant quickly. In good old Tetris fashion, tiles fall from the sky and stack up. It's up to you to get rid of them. You rid them in the same way you would in Puzzle Mode, but you don't have to do it in one stroke, although the more you get rid of with one stroke the more points you will earn for yourself. It starts off well, and once you clear the first few lines you will think you've hit gold with this game. But then bigger chnuks of tiles fall and the difficulty shoots up about ten notches. You will find yourself dying at the same point each and every time, and if you progress it merely becomes the next level of frustration. If it were a mode that had you constantly bettering yourself then there wouldn't be much to complain about, but with the way the tiles fall it becomes more a matter of memorising when the same old blocks are coming. The only saving grace for this mode is in multiplayer mode. When you clear your tiles they get sent over to their playing area, a bit of fun but a mode you each need a cartridge for which is disappointing considering what other companies have done with single cart multiplayer modes.