The Chosen Ones

Butcher's set+Destiny is the core, and doesn't even need a give up to pull off (Destiny can be obtained from chapter 10 lucky box with 0 luck). Of course using Oelivert makes it much much easier. Then you have Sword of haste of course which helps you also with ramping up the damage.
As i found recently Family picture from Phodom starter pack would be way better then Leviathan armour in a similar fashion (I never picked that item so i had no idea it can be activated to DOUBLE your attack speed, which is crazy).
I suggest to buy Life earring too from chapter 7 to gain an additional 400 life regen in chapter 10, then jewel of health, Andenaj I, II and III (II into III in chapter 7 also) and Francisca.
In the Zylcious fight I farmed the damage on Zylcious first form for some minutes, since he's immortal until you deplete his mana, then you cut through death knights and even Super Ummuut in a few minutes.
Of course you need to hit Fradz with Galeoth from time to time in order to keep the bonus when you can't hit anything with Fradz himself (and that's the reason you see he has no mana in the picture). You may need to have Sargatanas or maybe just Oricalchon equipped on Galeoth though, no idea why.
Of course Galeoth and Phodom serve the only purpose to support Fradz with buffs such as Zocmo's aura or debuffs (Doom Helmet from chapter 6 decreases enemies armour by 10, Santoryou does basically the same and so on).
Fradz's healing spell is actually bugged, I picked it just for testing, so blessing of lightning is still the better choice there. Not a big deal anyways.
I even discovered a new bug, i believe, I don't know if it's specific to this build.
When you reach 110k damage more or less, the game brings you back to like 10k. I checked the multiboard and Fradz Health Regen was still 110.000 or so, and should be always equal to his damage thanks to destiny...
Of course we have no way to check if this is always the case since this build is the only one capable to reach this amount of damage as far as I know.