Neverwinter Nights was released in 1991 and required players to pay hourly fees to play the text-based online game over slow modems. Ultima Online, released in 1997, was a massive hit that featured 3D graphics, communication between players, housing, and earning in-game money. World of Warcraft, released in 2004, was also instantly popular for its large 3D fantasy world with highly customizable avatars, detailed environments, and competitive gameplay aimed at leveling up through combat with other players and wildlife.