Beware the Ides of March! Actually, you might not need to "beware" it, though you may want to consider calling in sick from work or school -- Halo: Reach's first major expansion, a three-map DLC pack titled "Defiant," will arrive on the Xbox Live Marketplace on March 15 for 800 Microsoft Points ($10).

Check out the gallery below and the trailer posted after the break to get an idea of what the three new arenas -- named Condemned, Highlands and Unearthed -- look like! We really, really hope they come with the aforementioned trailer's gruff-voiced narrator. "Way to totally shoot that dude," the narrator would say, gruffly.