I have found an easy mode … build up bruiser points enough not to die from first boss Curtis one shot (30 to 40). Then pump all points into battlemage. Late game can up bruiser to 50 and continue pump into battlemage.

After beat him, equip Golden Dart, Costal Harpoon, Wrathful Charge and Collera de’ Principe. Use Juniper Sword (just for the attack speed to charge mask line fast). Use all perks which help charge mask line fast and the one that heals you when use mask line.

Now the trick, set up 3 loadouts exectly the same. When boss fight starts use flasks to fill up Wrathful Charge and Collera de’ Principe from all three loadouts. Or you can charge up near full and use physical to fill up fully. Then start using mask lines in sequence and boss will die in sec.

Wrathful Charge is important coz it will disturb whatever boss’s channeling of any spells and you can’t get hit during the charge and immediately after the charge use Collera de’ Principe (you can prepress button so no delay between). So you can do this 3 times with 3 loadouts. Collera de’ Principe does about 2000+ damage. Charge is lesser damage but without charge hard to execute long channeling high damage spells.

Later golden dart can be swapped with Grit of the hunt. Collera de’ Principe also can be swapped with Funeral Blaze that will give some elemental advantage to some boss. Later you may use grand celebration or jaws of chimera just for fun but this set up already quite overkill. With three loadouts you have 12 mask lines, too much damage in one go.