So I lost to a deck similar to this one and I thought I would try it.  It plays like Mecha'thun Druid but it seems easier to me.  You don't have to clear your hand/deck, although you usually want to draw as much of your deck as possible.

I saw 24 cards from my opponent.  The six cards I added were: a second Pounce and Gadgetzan Auctioneer, two Ferocious Howls and two Branching Paths.  These cards seem to fit the overall "miracle" draw style of the deck.  

Mulligan hard for Gadgetzan Auctioneer....prob Jade Blossom too.   I'll also keep Ferocious Howl and usually the Lesser Jasper Spellstone.  If you have Gadgetzan Auctioneer, I'll often keep 0 drops or Biology Project assuming you aren't playing against an aggro deck.

You usually start your cycling on turn 6 if you have Gadgetzan Auctioneer and ways to draw (0 mana spells, etc).  Be careful with Ferocious Howl while Gadgetzan Auctioneer is on the board...you often have 9 cards in your hand at this point so it can be easy to overdraw. Branching Paths can be dangerous too.   Remember to save one coin or Innervate to set off the combo.

Use Branching Paths to draw if necessary, otherwise usually use it for armor.  Sounds pretty obvious, right?

I've only used Jepetto Joybuzz once so far, but he's pretty cool.  He will draw you two minions if they are stuck in the bottom of your deck and you're ready to start the combo.

The combo is play Aviana, coin or Innervate, Kun the Forgotten King, King Togwaggle, maybe Jepetto Joybuzz, maybe a Naturalize or two, then Azalina Soulthief and check out your opponent's hand.  At this point, they often concede.

If your opponent has 8 or more cards in hand, you can play the combo but Naturalize before you play King Togwaggle.  Now he won't have King's Ransom to get his deck back.  You often don't need Azalina Soulthief for this method, but she's usually good to play anyway.

Jepetto Joybuzz may be unnecessary.  The deck may perform better with a Living Roots, Wrath, Claw, or maybe Crystal Power instead.   I would try Living Roots first.

First 12 games.....62% at rank 5.  I'll try to update in the next few days....This Deck Feels Great so far.

UPDATE - 7/30/19

45% after 45 games ~ rank 5.  Let's try some changes:

-2 Jade Blossoms, - Jepetto Joybuzz, +2 Wraths, + Coldlight Oracle

Jade Blossoms were the worst performing cards. Jepetto Joybuzz was almost a non-factor/wasted spot.  So I'm trying two Wraths and a Coldlight Oracle.  I try to save Coldlight Oracle for the end to help mill my opponent, but it can be used early to draw. Wrath can be used to draw as well, or take out a pesky minion like an Underbelly Angler.