Symphony is an ideal experience for that peculiar crowd of people who switch on their own music when they start up a game; in this case, it's a mouse-controlled shooter that uses your personal music library to generate custom levels. It's not the first time a developer has orchestrated this waltz between arcade shooters and personal music, though; tackled it in 2008 (although the setup was more like F-Zero than Galaga), and revived the concept in 2010. But rather than rehashing familiar themes, Symphony distinguishes itself through the appeal of its design, which channels the glowing neon aesthetic of Geometry Wars and pads it with an impressive range of upgrade options. It's not without some flaws, but its energetic gameplay and ever-changing levels render it well worth its $9.99 price tag.
You'll never look at an equalizer the same way again.
If you don't have mountains of albums in your hard drive, Symphony comes with its own selection of 21 indie music tracks from 10 different artists that range from fast-paced dance tracks to somber piano solos. Most are designed to ease you into the experience with their comparative mellowness, and thus it's much better to push the game's limits with your own high-octane tracks. Relentless beat sprees like New Order's "Confusion" rain down waves of enemies with all the force of a freight train, and even U2's "With or Without You" poses a challenge with its dogged bass line and crescendos. It's a nice touch, since the resulting gameplay excels through shifts between the predictability of the song you're listening to and the fairly unpredictable challenges of the enemies the song produces.
Considered solely as a shooter, Symphony is fun but only a couple of notches above average. Each song generates a level that looks and plays like a classic arcade space shooter in the vein of Galaga (although with a boxed-in arena-style presentation), complete with enemies that hurtle menacingly at your ship and barriers that cause instant death when touched. As with all such games, unfortunately, it's sometimes hard to see the ammo pumping out of your opponents' guns amid all the explosions on the screen. The good news is that dying itself isn't a problem because of infinite lives; what hurts you is the loss of a good chunk of the "inspiration" you pick up after killing enemies. This inspiration allows you to repair your ship and its four guns in the heat of battle, but more importantly, it's the currency for the upgrades you can snag after each round.
That's where Symphony comes into its own. Completing each song grants you the chance to purchase a single boost or weapon for your ship's four slots with your inspiration, and since the process is completely random, you won't have to worry about sitting through one type of song to get a particular item. Sometimes the item may be a "subwoofer" that draws its firepower from your music's bassline; at others, it could be a scattershot cannon that spits out ammo in a broad arc. The only drawback is that the list of upgrades gets impossible to manage after you've been playing for a while--since each upgrade is attached to a specific song, finding that crescendo weapon when you have enough inspiration to buy it largely on how good your memory is.
The five different boss types pose a significant threat on the hardest difficulties.