At Any Cost
From Halopedia, the Halo wiki
At Any Cost is the sixteenth track (Disc 2 Track 9) included in Halo: Reach Original Soundtrack.
The track is a remix of Sword Control (from the earlier track ONI: Sword Base), featuring the same percussion part but a different melody from strings and brass. As the melody repeats, the piano join in with short snippets. The track ends with a piano solo which gradually fades out.
At Any Cost is a bonus track found exclusively in the soundtrack, and thus cannot be heard in any part of Halo: Reach.