ODST is the winner. They really took a risk with that completely unique approach to Halo music. It was the opposite of formulaic. I would post highlights but the entire bloody thing is brilliant.
I also have to speak up for Halo 2, because it's my pet favorite and I don't think many people appreciate it. Halo CE and 2 had this chill ambient take on music that they completely abandoned in all subsequent games, much to my chagrin. CE had
A Walk in the Woods, which paved the way for
Heretic, Hero in H2, which is my favorite track in any Halo game. I love these songs for their match with the awe-inspiring environmental design, and for their contrast with the action gameplay. The mood actually gives me a confidence boost as I fight off enemies. Tracks like this made me like Halo in the first place and I'm sad they don't use them anymore.
Halo 2 also has plenty of other bits of brilliance,
Rembrance and this menu music,
Heavy Price Paid.
Halo 3 was ok but it started to show signs of just using block-bustery emotional dog-walking. The first mission had a trace of the old ambient feeling still in it (
Released), but I can now see that this was where it started to fade from the series. Some nice songs in the menus but I think most of them actually were copied straight from H2. This is the only track I really like that came from H3 -
Never Forget. That triumphant piano theme from campaign is nice once, but it is repeated waaay too many times for how simple it is. Like everytime you beat a level... daaaa.... da da! Da DA! It reminds me of beating a level in Mario brothers.
Reach matches the action but the wonder is gone.
Halo 4 makes me think they don't give a shit about the music anymore.
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