Containment Priest is a weaker answer to Living End than it first appears: because Living End's resolution sacrifices all creatures you control (including Priest) before putting the exiled creature cards onto the battlefield, Priest is already gone by the time their creatures would enter, so it does not exile them. Surgical Extraction can still proactively exile all copies of Living End itself from their deck once one is put into the graveyard after being cast via Shardless Agent or Violent Outburst's cascade, or strip a key cascade enabler. Fatal Push is weak here since their relevant creatures mostly only matter after Living End resolves, and while Stubborn Denial can counter Living End on the stack since cascade casts it as a noncreature spell without paying its mana cost, we can trim a copy. Keep Thoughtseize to strip a Living End or cascade spell proactively before they can go off.