Soundtrack composed by Frank Klepacki
Wow. Here we go. This is about as metal as you can get, which I think is a hallmark of Frank Klepacki's music (although to be fair, he is quite a versatile musician, able to compose music in a variety of styles and genres).
Speaking of metal music and "Haunt", there's apparently a heavy metal band hailing from California that also shares the same name as this track. And that's really all I've got to say on this track except I think it's a real headbanger and it's got an infectious beat.
The soundtrack was originally offered for free off the Petroglyph forums but you can download a copy from the Free VGM section at Choicest Games. It's also available for streaming off Frank Klepacki's website.