This checkpoint took me around 6 hours to beat. Should have beaten it much sooner but was fucking around with the machine gun when I should have been using the anti armor pistol for headshots from the beginning. The LFE also worked much better than the shotgun for interrupting burns when he gets close. The placement of the 3 hand grenades in the beginning is crucial and if it goes well all marines will be wiped out , isolating burns. I will break everything down further in the tutorial. Thanks to TheRipper999 for the LFE tactic.
This might not be a real "Boss Domination" as the playlist implies, but just beating this form takes alot, especially with low damage and quickly.
This is a clip from my upcoming God Hard Mode tutorial. Next up is the final bosses which will likely take MUCH longer with the method Im planning to use.