Yes, this is the one game I missed out - technically it was released before E3 so doesn't come under their umbrella and thus was worth mentioning on it's own.
The story takes place between Halo 3 and Halo 4 and features Sarah Palmer (a minor player in 4's campaign, but a major player in 'Spartan Ops') as well as a mysterious 'Spartan Davis' as playable characters.
The game is a top down shooter for Windows phones tablets and devices running Windows 8. I still run Windows 7 so unless there's a port for iOS sometime in the future you won't be hearing much about it from me for a while. Nonetheless it's exciting to see 343 branch out to more media, also announced is a new comic series 'Initiation' featuring characters from this game.
That's about it - I'll leave you with the trailer which features gameplay and samples of cinematics, done in the same style as Halo 4's terminals.
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