How To: Defeat Grimskull and earn 'But I Am Finished With You' in WH40k: Space Marine

Not only will this Giant Bomb Warhammer 40000: Space Marine guide help you beat Warboss Grimskull, it'll also help you unlock the 'But I Am Finished With You' achievement for the Xbox 360 as well. You will need to dodge the boss over and over again to survive, and keep your stamina up as there are four stages to this boss fight.