Myst Online: Uru Live is an open source massively multiplayer online adventure game developed by Cyan Worlds. The game is the multiplayer component to the 2003 video game Uru: Ages Beyond Myst. Like Uru, Myst Online takes place in 2000s New Mexico, where an ancient civilization known as the D'ni once thrived. The D'ni had the ability to create portals to other worlds or Ages by writing descriptive books of the Age. (wikipedia.org)