Osu

osu! is a freeware rhythm game originally for Microsoft Windows. It is written in C# on the .NET Framework. The game has also been ported to Mac OS X, iOS, and Android. Its gameplay is based on commercial titles including Osu! Tatakae! Ouendan, Elite Beat Agents, Taiko no Tatsujin, beatmania IIDX, O2Jam, and DJMax. Despite the stupidity stupidity of some; it is pronounced Oh-Sue. Not OOS.