osu! Ainu client is a private, third-party modification of the original
Integrated Private Server Support: It includes a built-in "Server Switcher" enabled by default, allowing users to connect to private servers like Ainu or Kawata.
| Feature | Osu Ainu Client | Osu Lazer (Official) | | :--- | :--- | :--- | | Input Lag | Near-zero (raw USB) | Moderate (SDL2) | | FPS Cap | Unlimited | Limited to Refresh Rate + 2 | | Multiplayer | Broken/Desync | Fully functional | | Skinning Support | Legacy only (.ini) | Full new skinning engine | | Score Submission | Bannable | Official | | Mods | Standard + Tournament | All standard + new mods (Freeze, etc.) | | Platform | Windows only | Win/Mac/Linux/iOS/Android |
McOsu is a legal, standalone practice tool that allows you to enable Relax, Auto-pilot, and even slow down time (Timewarp) for training only. It does not connect to the official osu! servers or submit scores. It is the perfect sandbox.
Built-in Server Switcher: Enabled by default, allowing easy connection to the Ainu private server without manual configuration.