Wizard101 is a massively multiplayer online fantasy game for children from Texas-based game developer KingsIsle Entertainment.

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The company inked a deal to bring its "World of Warcraft" online fantasy game to China seven years ago.

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One online fantasy game, Lineage, features 50 worlds, each so big it takes six hours just to walk from one end to the other.

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On March 16th 1999, a Sony-owned video game studio called Verant Interactive released a 3D, fantasy-themed online game called EverQuest.

FORBES: EverQuest Celebrates Fourteen Years

In 1997 the Origin Systems studio in Texas released a medieval fantasy game called Ultima Online.

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MLB.com offers fans the most complete baseball information and interactivity on the web, including up-to-date statistics, game previews and summaries, extensive historical information, online ticket sales, baseball merchandise, authenticated memorabilia and collectibles, fantasy games, live full-game video streaming and in-progress and on-demand highlights, live and archived audio broadcasts of every game, Gameday pitch-by-pitch application, around-the-clock hosted and specialty video programming, complete blogging capabilities and the award-winning suite of At Bat mobile applications.

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Thousands of giant online fantasy worlds are populated by real people interacting virtually, often representing themselves with animated characters in a blend of game play and chat.

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