How to incrase HP of bosses for D2R Randomizer?

Hello,

Is there a way to increase HP of bosses such as Uber Duriel, Izual, Lilith, Baal, Mephisto and Pando Diablo? Monsters HP is increased and so is my damage which kills those bosses with 1 hit.

For example, my summoner necro's skeletons kill those bosses with 1 hit. So, anyway to increase HP of the bosses?