- last post: 01.01.0001 12:00 AM PDT
When you buy Halo 3: ODST, you get 2 discs. First is ODST campaign, Firefight, Theatre and Extras, which allows you play in the Halo: Reach beta.
The second disc is Halo 3, sans Campaign. It includes all of the achievements for TU2, every single map released via Xbox LIVE marketplace and any updates made to the game. The new maps aren't ODST maps, they are new Mythic Maps. ODST's achievements and Halo 3's achievements are not connected together.
ODST's Vidmaster Achievements allow you to unlock Recon. They are obtained on Xbox LIVE. Once you have unlocked the Vidmasters, you get a code on your Bungie.net profile (or something along the lines of that-its in the ODST project page under "Road to Recon") which unlocks your Recon armour for use.
In Firefight, you can customize your ODST's armour.