You can tell by the sound he is most likely playing with a pick

E RIFF:
G----------------------------|
D----------------------------|
A----------------------------|
E-0-0-0-0-0-0-0-0-3^-0-0-0-0-|   just a driving bass line. super tight with drums

E
E0-0-0-0-0-5-3-0-0
Evariations                OR EVEN HITTING THE D TO D FLAT, OR THE E TO D ON THE A 
THE KEY IS TO KEEP THE LOW E ON BEAT.
E-0-0-0-3-5-0-0-0-0

G--------------------|
D------5-------------|
A---5---75-75----5-7-|
E-57-7----7--75-0----|   OR YOU CAN PLAY SAME RIFF BUT HIGHER STARTING ON THE

12TH FRET A STRING. INSTEAD OF 5TH FRET E STRING.

THEN GO TO C#, BASICALLY SAME FEEL BUT WARREN THROWS A LICK IN.
C# RIFF
G-
D-
A-4-4-4-4-4
E--

LICK:
G---------------------------------|
D---------------------------------|
A-4-4-4-4-4-4-7-7-4-4-4-4-4-4-4-4-|
E----------------7-0--------------|

BACK TO THE E RIFF
BACK TO THE C# RIFF

GOOD LUCK AFTER THAT. ILL POST THE REST LATER