It is online-only and played by thousands of simultaneous users (who pay a monthly fee) on various game servers, also known as shards. Ultima Online is a fantasy role-playing game set in the Ultima universe. The success of Ultima Online opened the door for the creation of many new massively multiplayer games. The game is played online, in a fantasy setting similar to that of the other Ultima games that preceded it.
It was instrumental to the development of the genre, and is still running today. Ultima Online (UO) is a graphical massively multiplayer online role-playing game (MMORPG), released on September 25, 1997, by Origin Systems.