Level Music by Sonic Mayhem
This particular track you hear is Track 9 on the Quake II CD-ROM; the game incorporated Red Book Audio meaning you could play the soundtrack in your regular CD music player. It's called "Descent into Cerberon" and it's definitely one of my favourites. A great track to get the adrenaline pumping, the track's title alludes to what is considered the capital city of Stroggos called Cerberon.
And that's all folks for Quake II, we'll move on to another game next week :).