Hearthpwn

This deck has been working really well for me at lower ranks: started my month's climb from rank 15 yesterday and this deck has got me to 11 in about two hours (hardly a massive achievement I know) with a current score of 12-3. 

This is basically just regular midrange Hunter but this time with Desert Camel and Injured Kvaldir added in instead of some of the spells like Quick Shot and Hunter's Mark, which gives the deck a more Zoo-ish feel. Getting two 2/4 minions on turn three is excellent tempo, even if the Camel gives your opponent a minion too. Even getting Webspinner from the Camel is good value!

There are thousands of Midrange Hunter mulligan guides out there, and it really doesn't change much for this deck... You're looking for one and two drop minions (NEVER KEEP Injured Kvaldir OR YOUR CAMELS WILL BE SAD), keeping three drops if you have the coin or a good curve anyway. Always keep Desert Camel on coin and also off coin if you have a sticky two drop. 

A Couple of Class Specific Mulligans: 

-Warrior: Keep Savannah Highmane on coin if you have some early game to go with it: Highmane is MVP against most Warrior variants. 

-Priest, Mage, Druid, Shaman: Keep Knife Juggler regardless of whether or not you have the ability to combo with it. These four classes all have a one or two drop that has three health (Mana Wyrm, Tunnel Trogg, Northshire Cleric and Darnassus Aspirant) which our other two drops don't trade well with. 

-Mage, Druid, Rogue: many people say not to keep Webspinner against these classes because they automatically die to an opposing hero power. This is exactly the reason why I think it is a strong card in these matchups: they waste their entire turn 2 removing a 1/1 minion that will then refill your hand so you can keep applying pressure. you then have the initiative to play a Mad Scientist or similar onto an empty board on your turn two. Also, keeping Webspinner in every matchup is particularly important in this deck because it gives you a 66% chance of getting the Injured Kvaldir that you want from your first Desert Camel!

The trap lineup is experimental at the moment: I chose Snake Trap to get more value out of Knife Juggler in the absence of a second copy of Unleash the Hounds and it's worked pretty well so far! Value with the snakes and Houndmaster is also a thing.... Freezing Trap is a Midrange Hunter standard: the tempo it can give you is amaing! If you're getting run over by cancerous Shamans and Scum Hunters, switching out both traps for one Explosive Trap and one Bear Trap should help you to slow them down. You can double up on secrets if you so desire, but I wouldn't recommend doing so because I prefer to have a higher chance of getting value from both copies of Mad Scientist but it's really down to personal preference. 

This deck is a blast to play (who doesn't love beating their opponents with a BADASS CAMEL?!) and seems to be hitting the meta in a decent spot right now... Whether or not this will change soon depends entirely upon whether the deck get popular enough for opponents to tart teching in Injured Kvaldir to mess up your Camel plays or not, but until then try this deck out, you won't regret it!

EDIT (15/12/15): 

-1 Webspinner, -1 Snake Trap

+1 Explosive Trap, +1 Freezing Trap

After taking on board feedback, I decided to tweak the deck a little to improve the odds of getting Injured Kvaldir from Desert Camel by removing a Webspinner, this frees up space for a third secret and therefore allows us to get even more value from Mad Scientist. Snake Trap also had to go: I felt it was too combo oriented and wasn't valuable enough when you didn't have a Knife Juggler, so I've added in a second Freezing Trap (it loves to bounce back Mysterious Challenger) and an Explosive Trap because I've been encountering lots of Secret Pally and Aggro Shaman on EU ladder and need the more controlling option against these decks.