Harmonix’s music series debutedt on a portable device with Rock Band Unplugged. Based on the same gameplay concept as Rock Band and Rock Band 2, Unplugged adapts the image for play via buttons rather than instrument controllers while preserving most of the playing modes and settings found in Rock Band and Rock Band 2.
The main game feature is Tour mode, in which players form a band and tour through cities, performing setlists to earn fans, money, and stars while unlocking new songs and venues. In the in-game store, money may be used to hire staff and outfit, band members. Songs that have been opened can be played in Quick Play mode without the requirement to form a band.
When a song is being played, the player controls all four tracks: bass, drums, vocals, and guitar. The four tracks are shown side by side and can be switched anytime. Each is made up of four note tracks that are assigned to buttons on the left and right sides of the display. The concept of phrases is added to allow performing a complete song conceivable in this manner. A phrase is a brief piece that is played on a single track. The way will play independently when all the notes in a phrase are played. Completing a phrase raises the score multiplier and relieves the player of strain because not all tracks must be played simultaneously. Failing phrases, conversely, can cause an instrument track to fail and, ultimately, the performance to forget. To bring back fallen instruments, the other devices can use Overdrive, which works in the same way as it does in other games in the series: when a series of bright notes are played, the Overdrive meter fills up until it can be activated at the press of a button, increasing the score multiplier and bringing back bandmates. During solos, the music in question is automatically picked, and the solo must be played in its entirety, with no phrases or switching allowed.
Submenus provide access to additional playing modes, which do not include phrases. In Band Survival Mode, the audience meter will gradually decrease for tracks not currently being played. Only the presently played way is of interest in Warmup mode, which can lead to failure if not enough notes are touched. Additional menu settings include unlocking all songs, removing solos, and a never-fail manner.
On-disc, the game includes 41 licensed tracks (all master recordings), most of which are re-used from previous games in the series. After Unplugged exclusivity, nine tracks were added to the game as DLC for the console versions. Fifty-seven more Unplugged tracks were made available as DLC via PSN through an in-game store in 2009.
