My favorite card in this expansion so far is Anka, the Buried because this card by itself is pretty powerful for what it is and has a lot of potential for some combos/decks to make with and let me give you a few examples :

Anka, the Buried + Mecha'thun + Backstab : The main goal right here is to have your Mecha'thun in hand and play Anka, the Buried to transform it into a 1/1 that costs (1) and you have to get rid of every single card you have in your hand, deck and battlefield expect Mecha'thun + Backstab so that you can combo with Mecha'thun + Backstab and you win the game well played !! O

Anka, the Buried + Mechanical Whelp + Necrium Vial : Right here on turn 5 if you have Mechanical Whelp in your hand we play Anka, the Buried to transform our Mechanical Whelp into a 1/1 that costs (1) and on turn 6 we play Mechanical Whelp + Necrium Vial to summon two BIG Mechanical Dragon!! That's pretty cool right ?!

Anka, the Buried + Anubisath Warbringer + Necrium Vial : Same thing again expect you need a bunch of minions in your hand to make this combo work.. Otherwise that will do nothing at all.. Sooo you play Anka, the Buried on turn 5 to transform our Anubisath Warbringer into a 1/1 that cost (1) and after THAT on turn you gonna play your Anubisath Warbringer and Necrium Vial and boom give all minions in your hand +6/+6. That's pretty broken when you think about it except when you have no minions in your hand.. 

Anyway that's why I love this card so much because so many cool interactions/combos you can make with !!

Thank you kindly sir.

Sorry to make a thread just for that..