We're Burning Sunshine
From Halopedia, the Halo wiki
We're Burning Sunshine is the ninth exclusive track in the Halo Wars: Original Soundtrack Bonus DVD.
The track opens with strings playing short notes before brass enter as the melody. The melody turns graver before heavy percussion take over briefly. Strings play in triplets, followed by vocals singing the first two phrases of the Gregorian chant from Halo Theme. Strings cut in shortly before resting, followed by a short cue by brass. Strings and woodwinds return in a heavy melody, followed by the first phrase of the Gregorian chant, but the melody does not resolve. Synthesizers return in eerie ambiance, soon joined by vocals and strings. They pause briefly before ending with a single note by piano. Strings and synthesizers return in ambiance, then joined by choir singing a graceful melody. The piece ends with drumrolls and a chord progression by piano.
The track plays in full during "Monsters", the beginning cinematic of the fifteenth Halo Wars campaign level Escape, when Red Team battles Sangheili and John Forge fights Arbiter Ripa 'Moramee at the Apex Site.
The name We're Burning Sunshine is a direct quote from John Forge during the cinematic, "Gentlemen, we're burning sunshine here".