Osu! Tatakae! Ouendan is a rhythm video game developed by iNiS and released by Nintendo for the Nintendo DS in Japan in 2005. Players control a cheer squad that supports individuals in distress, presented in a manga-style format. Players tap on the touchscreen in time with Japanese pop music to score points, with a focus on precision and rhythm. The game gained popularity outside Japan, inspiring the spiritual sequel Elite Beat Agents and a direct sequel, Ouendan 2.
Osu! Tatakae! Ouendan, or simply Ouendan, is a rhythm video game developed by iNiS and published by Nintendo for the Nintendo DS handheld game console in 2005, for release only in Japan. Ouendan stars a cheer squad rhythmically cheering for various troubled people, presented in game in the style of a manga comic. In each stage, players use the DS touchscreen to tap specifically marked spots that appear in rhythm to various Japanese pop songs, scoring points for accurate timing and avoiding a poor performance which can cause the stage to end prematurely. Though never released in Western markets, it was a popular import to these regions, leading to the development of the Westernized spiritual sequel Elite Beat Agents, as well as a direct Japanese sequel Moero! Nekketsu Rhythm Damashii Osu! Tatakae! Ouendan 2.
Source: Wikipedia.