World of Warcraft's third expansion will be released on 7 December.
Blizzard, creator of the hugely successful online game, confirmed the date as rumours of a December release swirled around the internet.
The expansion will re-make some of the original territories of the Warcraft world and introduce two new races.
It will also overhaul some of the basic mechanics of the game and give players a chance to make their characters even more powerful.
World of Warcraft (WoW) is an online game in which players create characters, such as warriors, warlocks and shaman, who they then take on adventures to gather loot and items to make the avatars more powerful. WoW is among the most successful of the so-called massively multi-player online games.
The expansion - called Cataclysm - will be available worldwide on 7 December and players will be able to buy it in shops or download it from the Blizzard store. The retail price for the expansion will be 34.99 euros (£30). A collector's edition will also be available only in shops for 69.99 euros (£60).
As the name of the add-on implies, Cataclysm will make big changes to Azeroth - the world in which the game is set. These changes are caused by the return of a dragon called Deathwing.
The expansion will also raise the level cap to 85 from 80 and introduce the goblin and worgen playable races to WoW.
To get at the content in Cataclysm, players must already have an up to date copy of World of Warcraft. Earlier expansions for WoW were the Burning Crusade in January 2007 and The Wrath of the Lich King in November 2008. | 
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