Audiosurf is an IGF Award winning puzzle/rhythm hybrid game created by Invisible Handlebar. Its track-like stages visually mimic the music the player chooses, while the player races across several lanes collecting colored blocks that appear in sync with the music. The game was released on February 15, 2008 over Steam; the full version is only available for purchase through Steam. Audiosurf is the first game to use Valve's Steamworks technology.

In Audiosurf the player controls a levitating spaceship-like craft similar to those found in Wipeout or F-Zero. The player then maneuvers it down a colorful multi-laned highway, collecting blocks in a manner similar to Klax. The ship is controlled either by a mouse, the arrow keys, the number keys, or a Gamepad. The game also supports the rumble feature of the Xbox 360 controller.

The music used in the game is chosen from the user's own library, from almost any DRM-free format, as well as standard redbook CDs; in addition, Audiosurf includes the entire soundtrack to the Orange Box as part of the download. An "Audiosurf Radio" tab is also included on the "Song Select" screen that allows the user to play the Audiosurf Overture, as well as a shifting selection of songs by featured Independent artists.

The goal of the game is to score points by collecting colored blocks (called 'cars') and forming clusters of 3 or more of the same color. The more blocks one accumulates in a cluster, the more points are scored. In the default color setting of the game, blocks which appear in hot colors such as red and yellow are worth more points, while cool colors such as blue and magenta are worth less. Players are also awarded bonus points at the end of each track based on feats they achieved. These include finishing the song with no blocks left in the grid or collecting all the blocks of a certain color. Each track for each difficulty level has three medals: bronze, silver, and gold. These are awarded upon reaching the point total required for them.

There are also additional game modes in the game where the goal of the game changes. For example, in the "Mono" game mode, players must collect the blocks, regardless of their color, and avoid the grey blocks. If the player can avoid the grey blocks until the finish he/she will gain a 30% bonus in addition to the sum of their points earned.

Upon completing the track, the score is uploaded to the score server together with the track length and form, any feats achieved, and the character used including the ironmode option if this was enabled. Scores are stored per song title, allowing people to compete. The uploaded length and track form make it possible to detect mislabelled or variant versions of songs in the score browser, and an option is provided to report possible fraudulent scores. There are three different high score lists for each song, for casual, pro, and elite characters respectively.

Originally Posted by Tiebasher

Wow this game is awesome. When watching the video I was like "HOLY CRAP, how are you supposed to hit all of those??", and then I realized that you had to hit only the colored blocks.