here's the theme that goes along with the Doom 3 PC game, written and
composed by Tweaker (Chris Vrenna).

Riff 1:   0:05
G|------------------------|
D|------------------------|
A|------------------------|
E|-0-0-0-0-0---0-0-0-0-0--|

Riff 2:   0:21
G|-----------------------------|
D|-----------------------------|
A|-----------------------------|
E|-0-6-7--6-7--6-7--6-7--0-6-7-|
(Note: not too sure about this, but it fits well with the song)


Riff 3 (Main Riff): 0:44
G|-----------------------------------------------|
D|------------------4-4--2-2---2-2-4-2-2---3-3---|
A|-3-3---3-3-5-3-3-----------------------------2-|
E|-----------------------------------------------|

Riff 4:   1:06
G|-------------------------------|
D|-------------------------------|
A|-5--3----5--3----5--3---3--3-3-|
E|-------------------------------|

Break:    1:21

Riff 5:   1:25
G|------------------------|
D|------------------------|
A|------------------------|
E|-0--2--6--2--4--3--2--3-|

Riff 3:   1:58

Riff 6:   2:27
G|-----------|
D|-----------|
A|-5-5-5-5-5-|
E|-----------|

Enjoy!