It may look basic on the surface, but underneath the simplicity lies a great racing game.
Although it is a racing game, Dotstream doesn't look like one initially. There are no cars, trucks, karts, boats or hovercraft in this game. Instead the six competitors in every race are pixel-thin lines, colored in a way that makes it look like a rainbow has split up to navigate a race course filled with simple shapes like squares and columns. All of the tracks could be easily duplicated in MS Paint—the courses are called drawings for a reason.
Given the simplistic graphics, it's easy to not take the racing seriously. In fact, the first two or three GP sets won't be that difficult if you have previous experience in the genre. However, when tracks get more complex with narrower passages, moving obstacles and more slow areas to impede your streaking line from getting to the front, you'll start to respect the circuits and race through them with more attention.
At the start of every race, your line shoots off more slowly than the others on the grid, making the game strictly a catch-up race. (This is actually a good thing, since the game would not be as challenging if there was a way to rocket ahead at the beginning.) Turning up or down will cause the lines to slow down some, allowing straight lines to pull ahead slightly. Straight lines cannot travel on top of each other, so if two want the same patch of track, the one that's behind will get pushed up or down until there's a clear lane for it to occupy. Navigating through narrow passages that have already been traversed by others is tricky business for that reason. (Check out the video of the game in action at Nintendo Japan's Dotstream game page to get a better idea of how the it works.)
All lines automatically travel forward at all times and at the same speed, but there are ways for yours to go faster than the others. Staying right up against an opponent's line will slowly build up a slipstream meter, and if it builds up enough, your top speed will increase. Two turbo boosts can be activated at will once the race is underway. Careful, though—any time you crash into an object, you lose one of your boosts, and crashing with no boosts in the bank ends your race. There is a pit lane in which you can recharge boosts, but it makes your line stop in place and allows the competition to streak by.
How you decide to go faster is what makes Dotstream a racing game of strategy. Do you want to burn off your boosts early to get to the front and avoid getting tangled up in the wakes of the other competitors, risking a race-ending crash? What if you decide to stay conservative and draft your way ahead while ensuring you have extra lives? Will the extra boosts gained in the pits be worth the time lost in getting them? Do you follow the path of the CPU lines to keep your draft meter up, or blaze your own trail that is less twisty? Deciding which strategies work with which tracks is what will hook you to keep at it. Figuring it all out and winning on the harder tracks is very satisfying.
If you need a break from the racing action, Dotstream has another game mode which has nothing to do with going fast. Formation mode is a parade or sorts, where you control a line and collect markers while navigating through a course. A meter fills at the bottom, and when a section is full, another line is added to the party. Up to seven lines can be in the group, but only one is directly under your control. Winning a GP series will unlock a command to help direct the other lines into more markers, and getting all the commands is the only way to navigate the course and completely fill up the bar. Learning formation mode is tricky, and the control options are a little complex, but once mastered you can create a symphony of sound and color. It's really neat.
Dotstream is a surprising game for the GBA. You would never expect such a simple-looking game to have such depth, but it does it with good gameplay, high-tension racing, and even some strategy to deal with. Even better for those who want to import, the game's text is 100% English. (Our friends at Lik-Sang can help you with that if you're interested.) On top of that, the game's box is really cool. If you're a pack rat like I am, you'll love the game even more because of it!