While it's easy to explain the concept of Sega's brilliant cat-and-mouse puzzle game ChuChu Rocket--players use arrows to guide cute little mice (ChuChus) into rocket ships and help them avoid evil, hungry cats--the game's appeal comes from a complex union of many small, simple elements that have been done very, very well.
The game's graphics and sound are both fairly rudimentary. The GBA version looks much like the original Dreamcast version of the game, which isn't saying much. Like Tetris and other puzzle games, graphic quality is a minor issue here. A major issue is that you can build, save, and actually trade homemade levels.
Most of the appeal comes from intense strategic frenzy. You've got to place arrows to redirect the fast-moving mice, and, hopefully, redirect any hungry cats that are on their way to eat your mice. This can get crazy in single-player mode, as you drop arrows and collect mice, approaching the goals set for each level. At the end of the level, when the timer runs out or the goal is reached, the rockets blast off and you proceed to the next level.
And though the single-player game is loads of fun, ChuChu Rocket really shines when you grab a link cable and connect with up to three friends. When all four of you are placing arrows to redirect mice into your rockets, and are directing cats into opponents' rockets (cats that enter a rocket steal mice, or points, from that player), you'll be laughing hard the entire time. There's nothing quite like it in gaming, and, best of all, you only need one game cartridge for the four of you.