They both had very different themes compared to the main story music. Reach had a ton of drums and beats, while ODST covered the rock and jazz.
I joined the Halo community later than most. I first got Halo 3 a few months after it came out and wasn't allowed to play it because of the violence. The Halo books are amazing, I suggest you read them. I've been watching a lot of Red vs Blue, and I'd love to make a machinima sometime if anyone is up. But the one thing I love about Halo besides the gameplay, story line, music, emotion, epicness, multi-player, and platform, is definitely the community (except you t-baggers, squeakers, spawn killers, and haters). I know that whenever I play Halo, I can meet the funnest people, and I think that is truly unique. Remember, feet first into Hell, and I'll see you on the battlefield!
Also, I would really like to point out that I was kicked off another profile Firedog340 because it was my stepdad's where I was a Hero in Halo Reach, and had far more completion on some Halo games.
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