Mutant Overlord

When Mutant Overlord enters the battlefield each opponent chooses one creature and artifact then returns the rest of them to their library on the bottom in any order.
Mutant Overlord then fights each creature on the battlefield, if a creature is put into the graveyard from this they sacrifice a permanent and Mutant Overlord gets +1/+1.
All bodies turned to ash, all relics turned to dust, accept you, I wanted you to survive so that I may show you what true strength is.