Note: This works with any boss mod (Regenerator, Skullcrusher, Vicious, Hearty, etc). Strats below.
www.twitch.tv/ClayM0hr
General strategy:
Hope the blooper at the start provided a laugh or two!
Try to time your dodges of the explodey children at the last possible second, and dodge AWAY from them. This will limit/nullify all the damage and prevent you from getting Root Rot.
For Gorefist himself, you want to dodge TOWARD his open hand when he's doing the running attack, and then try to stay away from him in general outside of that.
To simplify the fight a bit more, utilize the Rattle Weed Mod, which is obtained from murdering the evil tree that can randomly spawn in your campaign.
Don't be afraid to use your items, especially ammo boxes if you need a quick refill. Time your usage of items when there aren't any screaming children, and AFTER you've dodged his sliding attack and have run away from him a little bit.
Good luck!
Weapons Used:
Magnum Revolver
Hunting Rifle
Mods Used:
Decoy (Rattle Weed)
Armor Used:
Hunter Set (Doesn't do much here)