The main gameplay modes in Rock Band Unplugged are similar to that of the console versions of the game. In Tour mode, the player creates a customized band, plays sets of songs at venues around the world, earning cash and fame, and unlocking new vehicles, venues, and staff. Songs completed in Tour mode then become available in Quick Play mode, which allows any song to be played without the need to create a band.
Songs in Rock Band Unplugged feature tracks for the same four instruments as in Rock Band: lead guitar, bass guitar, drums, and vocals. During the Quick Play and Tour modes, gameplay is similar to Harmonix' previous games Frequency and Amplitude: The player presses combinations of buttons on the PSP to match notes in time with the rhythm of the currently-selected instrument. After completing a phrase without missing any notes, the instrument continues to play automatically for a set amount of time, allowing the player to switch to another instrument using the shoulder buttons.[3] Successfully completing multiple phrases in a row builds a score multiplier, as well as allowing the song to play in its entirety. Not completing a phrase in a track for an extended period of time will drain the Crowd Meter for that instrument, eventually causing the instrument to fail. A failed track will eventually cause the entire band to fail if not saved in time.
Overdrive is handled similarly to the main Rock Band series. By hitting certain white-colored sections of notes placed throughout a song, the player fills the Energy Meter. Once the meter is at least half full, the player may press down on the D-pad or X to activate Overdrive, which revives all failed instruments and enables a temporary state that boosts the score multiplier and slows the degradation of the Crowd Meter for all instruments. During solos, the player is automatically switched to the appropriate instrument; each note is scored individually, and the phrasing and track-switching elements do not apply until the solo is over.
Two additional modes, Band Survival Mode and Warmup Mode, are included in the "Extras" section of the game. In both modes, notes are scored individually, instead of being divided into phrases. Tracks will not play automatically, causing the Crowd Meter for unselected instruments to continually drop in Band Survival Mode. In Warmup Mode, only the currently-selected track is affected by missed notes. No multiplayer mode is included in the game.[4]