Hearthpwn

I've won over 30 Gift Exchange brawls in a row with this deck. Its a combo control deck.

Beginning hand you want to mulligan for Shadowstep, Crazed Alchemist, Pit Snake or Eviscerate.

The goal is to never let them get a gift prize through control. It's easiest if you start with coin but still easy. 

Combos/Plays:

Turn 1 Pit Snake almost guarantees you get first gift and clears anything else late game.

Crazed Alchemist can come out as early as turn one with coin and instantly you use it to clear your own gift creature and get a gift. You can also use Shadowstep same turn and replay Crazed Alchemist for their gift. (Always coin Crazed Alchemist if you have coin)

With coin you can also Eviscerate your gift turn one. And remove many creatures or get more gifts late game, focus on gifts.

Preperation into Beneath the Grounds is fun and cheeky 0 mana move. You'll have tons of other stuff to do with all the gifts.

Cold Blood can be used to boost any creature or grow your gift to clear creatures. Also tons of damage.

Use Buccaneer, Deadly Poison, to grow your weapon to clear creatures. Bloodsail Raider is great value, grows with weapon and pirate flavor. Southsea Deckhand also great for damage, clear, and works with weapon, also pirate. Dread Corsair also easy play with grown weapon and pirate. And all these pirate synergies with Ship's Cannon.

Defias Ringleader goes ok as combo value and shadowstep

Gifts to focus on:

You want to focus on getting any gifts to clear or bounce their minions. 

Hardpacked Snowballs are the best, 0 mana to bounce 3 of their minions. Prioritize this.

Shado-Pan Rider is pretty sweet if you're ahead, 0 mana for a 6-7

Vanish will be a 1 mana gift that bounces everything, lets you catch up and replay Crazed Alchemist to keep getting gifts and bouncing more.