Hearthpwn

Mulligan, no matter what, for Sea Giant & Cold Blood. Crazed Alchemist is another priority, especially if you pick up Shadow Step

If you get Sea Giant out in the first turn or two, don't use on the gifts; just go face.  I ground out my 100 gold for the day in about an hour. 

I can't imagine anyone wants a more elaborate guide than that, but if this gets some upvotes then I'll bother. Got some upvotes so I'll bother. ;) 

So obviously the goal is mow down gifts as quickly as possible, and to deny your opponent the same. This deck assumes that the best way to do the latter is use cheap legendaries gained from the former. 

Generally, you can get at least one gift on Turn 1—especially if  you have The Coin—and often two or more.  And, in general, the success of this deck comes from it's being really fast and able to dominate the board in the first two or three turns. I've actually won on turn 3 a few times (not with a concede, but all 30 damage). And there are a lot of synergies and combos that work, depending on your draw, out of the gate. So instead of describing all of those, here's a breakdown of why each card is included:

Backstab, Preparation, Counterfeit Coin and Shadowstep: All of these are here for combo triggers, first and foremost; you want to be able to use Eviscerate or Cold Blood on any turn you have them. The extra mana from Counterfeit Coin also frequently lets you get a gifted legendary out on turn 1 or two (ie. Had one game that went Prep->Eviscerate->Coin->Loatheb on turn 1). Shadowstep works best with Crazed Alchemist but don't be afraid to take a gift off the board if it triggers a combo you need.

Sea Giant will basically decide any game wherein you can drop it on turn 1 with a few exceptions.

Edwin VanCleef is in the deck because there are so many zero-cost cards which are really only present for the first few turns. They can sometimes collect in your hand and VC is a tidy way to part with them.

Eviscerate, Cold Blood,Shadow Strike and Crazed Alchemist are your instant-gift cards. 

Pit Snake, Patient Assassin and Envenom Weapon, aside from being solid ways to get those gifts, mostly serve to remove opponent legendaries and regain tempo. Pit Snake also frequently triggers a combo or drops the cost of Sea Giant by 1, letting you get it out on turn 1 with a coin, or, if your opponent dropped a minion first, for free.

Wailing Soul just denies your opponent their gifts. If your game lasts to turn 7, when the second deposit of gifts arrives, make sure you have this handy. 

Vilespine Slayer is most likely to see use on opponent legendaries, but feel free to pop a gift with it if the opportunity *presents* itself (badum).

Sap is great; makes your opponent pay the actual cost for their legendary.

Comment if you enjoyed. Have a Happy feast of Winterveil!