Playing against Rez Priest is a pain in the ass, and I think the Heroic bosses would agree!
I just beat the 4 explorers, they're super hard bc they keep tranforming the board into murlocs and it fills their hand with 0 mana murlocs. But I had 4 fully charged Lesser Diamond Spellstone(with shadow visions). They don't get countered by murlocs because the spellstone summons 4 "different" minions. So anyways, I started blasting them with the Kel Thuzads and Khartuts, whenever he cleared I played another spellstone, until they died