Music by Kevin MacLeod. Available under the Creative Commons Attribution 3.0 Unported license. Download link: https://incompetech.com/music/royalty-free/index.html?isrc=USUAN1100403

MacLeod's description:

Genre: Soundtrack
Length: 1:13
Instruments: Bassoon, Strings, Choir, Xylophone, Brass

Starts thin, and pulsing, ends giant and brass-filled.
ISRC: US-UAN-11-00403
Driving, Eerie, Epic, Intense, Mysterious, Suspenseful 2008