Hearthpwn

If you have Alexstrasza in your collection, add her to your deck. It will make the boss health down from 200 to 15. It will make things easier lol. But if you don't have it (like me haha), you can try my Resurrect Priest deck.

I'll be honest, It will take you a few tries before you make it. Getting Alarm-o-Bot early in the game will boosts your chances. I was able to summon Ysera at Turn 5. For removals, you can use Shadow Word: Death, Mass Hysteria, and Psychic Scream. Convincing Infiltrator is also handy for destroying his minion. Even Ysera's Dream is very useful by returning a minion into its owner's hand.

Then, resurrect spells are at your disposal. Keep on resurrecting your minions. Also, once you completed your quest, you can have both heals + buffs. Be careful with Skruk's Heartseeker, It will deal 15 damage to your hero. So watch out for your health. Good luck!

You can also check this video: