Courtesy of IGN:

343 has announced downloadable content details for Halo 4. Three map packs will be available including three maps each and are set to arrive between December 2012 and April 2013. Players will have the option of purchasing a Halo 4 War Games Map Pass for $24.99 (2,000 Microsoft Points) that will offer access to the packs at a 15% discount as well as a unique in-game Falcon emblem. The Map Pass is included for free with the Halo 4 Limited Edition, and two unique in-game helmets (Scanner and Strider) will be offered when the Pass is purchased separately.

The Crimson Map Pack will be released in December 2012 and includes three maps: Wreckage, Harvest and Shatter. According to 343, players will “witness the chaos of a clash of civilizations” in Wreckage and see a “blend of claustrophobic spaces and dangerous exposures.” Players will also “venture into the human colony environs of Harvest” and “explore a human foray on an alien moon in Shatter.” The Majestic Map Pack, due in February 2013, includes Landfall, Monolith and Skyline. As 343 describes, “Landfall’s emphasis is on infantry battles against a glittering ocean on a distant world, while Monolith exposes you to the naked vacuum of space — and the firepower of opposing teams. Skyline’s distinctly industrial feel provides new challenges in somewhat familiar, but occasionally confined spaces.”

Finally, the Castle Map Pack is scheduled for April 2013 and offers Daybreak, Outcast and Perdition. “Daybreak is set in a military facility against the backdrop of an idyllic mountain range,” 343 says, “while Outcast plunges you into the warrens, canyons and arches of an alien edifice. Perdition takes players into the heart of an urban sprawl, with tactical speed and situational awareness its key features.”

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You can also check out their Halo 4 concept art gallery here!