Guitar Hero On Tour: Decades is a music rhythm video game for the Nintendo DS, part of the popular Guitar Hero series. The game, developed by Vicarious Visions and published by Activision in 2008, enables players to experience a portable rock concert. They use a unique guitar grip accessory, plugged into the DS' Game Boy Advance slot, to strum along and hit notes as they appear on screen. It features a selection of songs from various decades, allowing players to engage with classic tracks and modern hits across multiple rock genres. Multiplayer modes enable head-to-head battles and cooperative play.