From December 17, the tournament will track gamers' personal scores in War Games and the number of Spartan Ops chapters gamers complete on global leaderboards, giving players of different preferences and skill levels the chance to win a range of prizes.
After a qualifier phase, players will be tiered into three groups based on results, and will enter the finals which go from January 12 to 19.
The top prize for the War Games leaderboard is a UNSC-themed, V8-powered 2013 Ford F-150 SVT Raptor truck, designed by 343 Industries.
In announcing the Spartan Ops winner reward, Xbox, in an official statement, has confirmed that the Halo saga will continue in stating that the grand prize "will be an appearance in a future Halo game."
The competition will also feature a series of weekly challenges with more prizes on offer.
The free-to-enter tournament is available to all gamers, and kicks off on December 17. Players can register themselves by visiting the competition website. Localised registration sites become available on December 12.
To make things more interesting, a Halo 4 Crimson Map Pack will be launched on December 10 on Xbox Live. It will features three new multiplayer maps (Wreckage, Harvest, and Shatter) which can be purchased for 800 MS points, or downloaded for free for gamers who purchased the game's Map Pass or Unlimited Edition.
Due to the launch of both the tournament and map pack, the regular Spartan Ops season will go on a break from December 10, and will resume "later in January" with new episodes, chapters, locations, and maps.
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