Halo: Reach players should be plenty experienced with the multiplayer battlegrounds found in the 'Noble Map Pack' (which we thoroughly enjoyed, by the way) so now is a good time as any to bring in some fresh levels. The upcoming 'Defiant Map Pack' offers two large maps plus a new Firefight stage for some co-op action.
The largest map, Highlands, takes place in a former top-secret Spartan training camp that's suited for Team Slayer, Team Objective, and Big Team Battles. Condemned pits up to 12 players in Orbital Station Gamma, a space station that's perfect for rounds of Team Slayer, Team Objective and Free for All. Unearthed is a mining facility being swarmed by the Covenenant so call in your friends for some backup.
Coming along with the three maps are new Achievements that can add 150 points to your Gamerscore. You can buy the 'Defiant Map Pack' for 800 Microsoft Points when it's released this March.