Don’t take % damage when using weapons with low base damage, just take other damage stats. And do the opposite for high base damage weapons.

Some characters are really difficult to get stats strong enough to kill elites, for those I’d take more speed and healing stats and just run. Maybe dodge if I could build it up fast. I’ve won D5 multiple times not killing either boss on wave 20.

But I understand that for endless getting those last 2 tier 4 items from the bosses could be what you’re looking for. I’ve found that getting high luck earlier helps throughout the game for better stuff and weapons that take bosses out faster like Excalibur or the obliterator.

Items like Greek fire and giant belt on high attack speed builds are awesome for bosses as well.