Knight Online is an MMORPG developed by MGame Corporation and Noah System. Currently there are many different companies that host this game by geographic region. Some are Free to Play while others are Pay to Play. Two major updates have been released for the Knight Online. In September 2005, a major update known as Knight Empire was released that changed a few maps, added new item upgrading systems, and introduced the King system into the game. On or about August 3, 2006 a new expansion called The Reign of the Fire Drake was released.

Some months later, a new expansion for the game was released: "Moradon: The Ressurection".

Generally, the older worlds are the most heavily populated and therefore impossible to enter for Free2Play players (see Criticism). Players are allowed to have up to three characters on each server, but all of the players on the server must be from the same race. To have one character that is human and one character that is orc, a user would have to make one of them on a different server