Hearthpwn

If you have not tried a deck similar to this I highly recommend you try one with this base model, it is important to use all the resummon and reborn spells

I prefer to keep all of my cheap spells at the start of the game some and others mulligan for 1 3-cost minion. The haunted, or the mind-eater. Prince Renethal is not bad even if you reborn/resummon/create 2 copies deathrattle spell him. For board control.

Combo's with the horse's deathrattle "destroy an enemy minion" work great as well as combos with the 3/7 taunt's deathrattle "deal 3 damage to all enemy minions"

Do not be afraid to combo reborn and deathrattle "resummon 2 copies of this - spell" with the 2/5 bone taunt. Because with Xyrellia that gives "cast all deathrattles played this game" you will summon a new minion for every time one had died. For example one game I could only summon the 2/5 taunt's with deathrattles "resummon a friendly undead that died this game". Pretty abysmal with nothing to resummon. I cast reborn and resummon 2 copies of this and had 5 of them. Just to hold off the enemy onslaught. But when Xyrellia comes in she resummoned 5 minions that died after that anyways and I still received GREAT value. 

If you use the 1-cost "give a minion reborn" it retains all of the prior enhancements. So that means if it has been buffed to a 10/10 it will be reborn a 10/10. Or if it has deathrattle spell "summon 2 copies of this"

I don't have all of the deathrattle and undead cards, but the deck has proved incredibly sturdier than all of my other decks I've ever played. I put this one together recently after a few years off from hearthstone.