The challenge for Halo and Black Ops is to prove they have something new to offer.

BBC: Halo 4 and Call of Duty: Black Ops 2 shoot it out

Black Ops 2 and Halo 4, the latter an Xbox Exclusive and the former mostly played on Xbox, had a lot to do with the still-impressive Xbox sales.

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Halo 4 and Call of Duty: Black Ops 2 are the biggest games of the year.

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That means it will avoid competing directly with big-budget first-person shooter rivals, including Halo 4 and Call of Duty: Black Ops 2.

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Black Ops 2 launched one week after the release of Halo 4.

FORBES: 'Black Ops 2' Tops 11M Units Sold In First Week, No Signs Of Call Of Duty Fatigue Yet

Armstrong's golden halo in the sport's annals has decayed to a black mark.

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"Offensive Combat" is a shooter that blends elements from the most popular shooters out there like Microsoft's "Halo 4" and Activision's "Call of Duty: Black Ops II" into a free-to-play experience that's fully customizable.

CNN: STORY HIGHLIGHTS