I was inspired by Poinas’s Pwning with Spirit Guide to create a similar health reduction build for GD.
My plan is to use a 2H weapon with the “of Annihilation” suffix and some jewelry with the “Sapping” prefix. Then layer weapon damage skills on top of each other to maximize concurrent health reduction from multiple independent sources. The best I can come up with so far is to max Upheaval, stack OA, and use a devotion skill with high weapon damage like Maul.
Another method would focus around maximizing Targo’s Hammer orbits. I’m not sure this would work better given the “of Annihilation” suffix isn’t as good for 1H weapons. And though it is less OA-dependant it is highly block-dependant.
I am aware that Heroes and Bosses have a separate resist for health reduction called, “Resist to Health Reduction.” That makes vitality resist reduction combos like CoF + DS useless. I was planning on using the “Plaguebearer’s” prefix + Mark of Dreeg + Sacred Strike combo for general flat resist reduction. Regular mobs probably don’t need resist reduction and if they do adding Acid Spray/Agonizing Flames/etc. in the mix somewhere would probably do the trick.
The only question remaining is, how much Resist to Health Reduction do bosses have? I hope it’s not 500%, otherwise this build is toast.