Welcome to osu!OpenRooms.
OpenRooms is an online osu! multiplayer lobby manager. It can be used to put on advanced playlists for your lobby, giving the players host in a much more configurable and fair way, sharing your mapsets, etc.
Create and share your map playlists.
You can create maplists which consist out of multiple maps and share those with your friends and the community. You could automatically fill maps based on data from grumd's pp maps site or you could make marathon playlists, tutorials for a game mode or collections of technical maps or other themes.
The playlists you create can then be used inside a lobby using the Playlist mode, giving the players and yourself the opportunity to easily play through your map selection and have fun together in multiplayer.