There's also a tournament described at the link.
Source: http://www.gamespot.com/news/halo-series-sales-hit-50-million-6401164Gamespot said:Microsoft has now sold 50 million Halo games since the series launched more than a decade ago with 2001's Halo: Combat Evolved. The company announced the news this morning, reiterating that players have spent more than 5 billion hours playing Halo on Xbox Live.
Prior to Halo 4's worldwide launch on November 6, the Halo series stood at 46 million in sales. This suggests Microsoft's newest entry has shifted 4 million copies thus far. Halo 4 generated $220 million in 24-hour revenue at launch, with $300 million expected for its first week.
Microsoft has released eight Halo games to date, all of which have been first-person shooters, with the exception of 2009's strategy game Halo Wars. These include Halo: Combat Evolved (2001), Halo 2 (2004), Halo 3 (2007), Halo Wars (March 2009), Halo 3: ODST (September 2009), Halo: Reach (September 2010), Halo: Combat Evolved Anniversary (2011), and Halo 4 (2012).
Bungie Studios created the Halo series, though the company has since moved on to an all-new franchise to be published by Activision. Microsoft's new 343 Industries label is now responsible for all things Halo, and is currently working on at least Halo 5 and Halo 6.
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