On each level in order to successfully navigate your two characters to the exit, you have to figure out the right sequence to do everything in. You only control one character at a time and both have identical abilities/limitations such as how high they can climb up to or down from.
By far the most common thing you do, is to push and stack blocks to help you get where you need to go. Other puzzle mechanics are: elevators, teleporters, magnetic blocks and lever-operated electromagnets, blocks that disappear if two are placed next to each other, lever-operated retracting platforms and more.
* Levels are well-designed and generally are quite challenging.
* Has a Quicksave/Quickload feature with three save slots, that lets you save your progress at any point during a level that you can reload at anytime later while still playing that particular level.
* Has a grid overlay you can click on or off at anytime that can help you see the exact distances.
* In the Help section, every puzzle mechanic and game technique has some text and pictures explaining its use.
* You can hit the Select button to directly bring up the Quicksave/QuickLoad feature instead of having to access it from the pause menu.
* Only marks that you solved a level and no other information such as total time taken or number of attempts is recorded.
* You unlock levels one at a time with the option to skip up to three levels, which means you can only have up to four unsolved levels at any one time unlocked.
* When using Quicksave/Quickload especially if you are utilizing all three save slots, you may have to pay careful attention to the labels since they are the time elapsed since you last hit save and since a file saved in a particular slot may well (at least in my own experience) be located in a different slot next time you open this feature.
In terms of level design and difficulty, this game is similar to Exit DS, so if you liked that one you will probably also like this one. Personally I think it is great and it is now one of my favorite DS brain puzzle games.
Also it is a wonderfully efficient feature to be able to save your progress during levels so you don't have to keep repeating the same first several solution-steps if you make a wrong choice later.
Some Additional Info:
The game is controlled entirely with the control pad and buttons(though you can use the stylus for the menus if you want). The puzzles can be on just one screen or sometimes they can take up both the top and bottom screens. The characters are a bit on the small side, being just two grid units high(each DS screen is divided into a 24 by 32 grid), so for some players this game might be easier to see and play on a DSi XL.