When Halo 2 was released, it was accompanied by a soundtrack. Unfortunately, it wasn't the soundtrack fans had been hoping for: instead of one featuring the music from the game, it instead pulled the old "music from and inspired by the game" trick. While a few game tracks could be found on it, including "Halo Theme Mjolnir Mix" and "Ghosts of Reach", it was also loaded with tracks by Breaking Benjamin, Incubus, and Hoobastank.

It was tolerable. The game-specific tracks were great, and a few of the "inspired by" tracks grew on you over time, but it wasn't the soundtrack we wanted.

Volume 2 is that soundtrack.