Piano Concerto No.25 in C major K.503 Wolfgang Amadeus Mozart
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Neil Davidge: Halo 4 Original Soundtrack - an album guide
Game soundtracks are renowned for being long, and it sounds like Halo 4 was no exception: "This is a complex evolution of the 'Nemesis' theme. The original production was around thirteen minutes long but I had to edit it down for the OST even though it still lasts around 7:20!"