The game is music-driven because that's still Harmonix's thing. "Level design and song authoring is done in parallel, insuring a hand-crafted and utterly unique audio-experience that only Harmonix can provide," Harmonix says. "Music drives player projectiles, enemy spawning, movement, and bullet patterns."
A City Sleeps is due out for PC and Mac on October 16 via Steam, and it's available for pre-order now for $12.75, a 15 percent discount. Harmonix recommends using an Xbox 360 gamepad (keeping that Microsoft relationship alive).