Rule 1: Don't get close to it after killing the bezerkers.
Rule 2: Have your target locked on to the bullzozer right before the
bezerkers show up and as the arm raises, jump up in the air and blast
away at the eye with the shotgun.
Rule 3: If you have no shotgun ammo, then try the other guns.
Rule 4: When fighting the bezerkers, don't let them surround you, do
combo attacks and jump attacks.
Rule:5: Repeat over and again until the thing is dead.
HINT: It helps if your shotgun's strength level is 2.