"I hate regenerating bastards like you!" Herold's incredibly huge armory was seen here as he was switching out weapons every now and then trying to find the right one. He has a dagger, a longsword, a spear, a rapier, lance, mace, flail, sickle, greatswords... Basically anything that identifies as a weapon type, Herold has it.
The most effective one on him is that greatsword. It was a perfectly balanced sword but its imbued with wind magic. A single swings knocks back that giant hunk of stone a couple of meters and breaks the armor surrounding its body.
But its insane regeneration and reforming is nearly impossible to damage it. Its stone armor changes depending on the situation.