Like Bizarre's two Geometry Wars titles, Boom Boom Rocket is simple and straightforward--though it offers plenty of challenge. Gamers familiar with nearly any music-based game will likely pick up Boom Boom Rocket's core mechanic quickly. As music blares, colored icons corresponding to the Xbox 360 controller's four face buttons scroll upwards. As they intersect with a horizontal bar at the top of the screen, the player must press the appropriate button in time. There is little to the game beyond this, but of course the enjoyment and the challenge comes in the execution more than the fundamental concept.

Helpfully, icons are color-coded and labeled not with their alphabetical identifications but rather with arrows indicating their actual spatial position on the controller--for example, an icon requiring the player to press X is blue and marked with a left arrow. This feature is enormously helpful, particularly for those--such as myself--who never fully internalize the symbolic markers on all of the various console controllers. Visually, this is all reminiscent of the PlayStation 2 launch game Fantavision. Like that game, it features cityscape backgrounds, with fireworks exploding as players successfully pull off moves. As in Geometry Wars: Retro Evolved, the events happening on screen are fairly simplistic, but the visual effects layered over them are attractively pyrotechnic and over the top.

On easy mode, button presses are isolated and come largely on strong beats, making the patterns fairly easy to follow. Moving up to medium difficulty adds some syncopated rhythms and introduces instances of needing to press two buttons simultaneously. These combinations are always of two diagonally--never horizontally or vertically--adjacent buttons, so it is less an issue of being able to physically press them effectively and more a matter of overcoming the mental obstacle of quickly recognizing which two buttons are required. The hard difficulty level ups the complexity of the rhythms and increases the frequency of double button presses, with intensely complex runs of simultaneous presses at frightening tempos.

Each music track has three uniquely crafted sets of patterns, one for each difficulty level. All of the music I was able to try was well known public domain material recreated in dance-friendly synthesized form accompanied by amusingly cheesy monikers. For example, Edvard Grieg's sinister In the Hall of the Mountain King from Peer Gynt is present as Hall of the Mountain Dude, Bach's legendary Toccata and Fugue in D minor is reprised as Toccata and Funk, and Tchaikovsky's rousing 1812 Overture makes an appearance as 1812 Overdrive. Beethoven is represented at least twice, with the first movement of his 5th Symphony (named Game Over Beethoven here) and the affecting first movement of the "Moonlight" Sonata No. 14 (redubbed Tail Light Sonata). The full track list contains numerous other works. Unfortunately, as far as I can tell, there is no mention in-game as to the original composers or titles of the pieces.

As is standard to most rhythm games, Boom Boom Rocket's standard mode simply plays through the selected track then presents an overall letter grade along with statistics such as accuracy, hit ratio, number of misses, and best consecutive hit run. There is also a multiplayer version of that mode that has two players facing off in the same track simultaneously to achieve the better score. Other modes include Endurance, in which players attempt to attain the highest time as the music loops indefinitely; Practice, which is unscored and does not allow the player to fail the track for any reason; and Freestyle, which has no rhythmic or scored element at all. In Freestyle mode, icons still float up but the player can press any face button at any time and receive an explosion. EA senior online product manager Kyle Murray explained that this is primarily intended as a toy for younger children whose parents may not be thrilled about the idea of teaching them the intricacies of rhythmic hand-eye coordination. Finally, the game includes a Boom Boom Rocket-themed music visualizer that will provide a light show syncing up to the beat of any of the included tracks or a player's Xbox 360 custom soundtrack.

Like Bizarre's Geometry Wars series, Boom Boom Rocket offers relatively few options but delivers satisfying core gameplay that is sure to appeal to fans of the genre. It is a perfect fit for Xbox Live Arcade and should serve well to fill the rhythm gap in the service's repertoire. Look for it this spring.