It is primarily a practice client for getting better at the 'official' game by having tools at your disposal that osu! does not provide for some reason, it's not supposed to be a perfect copy of osu!, or otherwise profit with a free game from a free game (what). About This Game McOsu is developed separately from and has no direct affiliation with osu! or ppy Pty Ltd.Ī free open-source circle-clicking rhythm game client for osu! beatmaps, with the main focus on making practicing easier and customizing gameplay.