Hearthpwn

Plan for a game that goes into fatigue. Save Alex for the end, limit your draws from Acolyte, and get into Shadowreaper Anduin ASAP so you can keep their armor low/gone.

I do believe the 2x Pyro is good. Not just for clearing Paladin boards, but also because you need some aggressive creatures if you want to win against Quest Rogue. 

This deck is insanely good. I have never felt such satisfaction from playing a deck since Secret Paladin. It feels like you always have an ace up your sleeve.

Against Quest Rogue you have to get aggressive from the start. I'm 3-2 against them right now with this deck. Drop those Wild Pyro and Squashlings on curve and race them. Baku Warrior you're in for the long game. Prepare for it to go to fatigue and plan accordingly. 5-1 against Baku Warrior.

As someone who consistently gets to rank 2-5 with Mage decks (never broke that Legend *tear*), I can say this deck does not work. I have been trying every incarnation of Elemental Mage possible.

Aggro runs you over without Volcanic Potion, but is useless in every other matchup
Priest is almost guaranteed an auto loss - their end game is strictly better and you'll rarely be able to race them in time
Jade Druid will always win if that single Skulking Geist is in the bottom 10 cards of your deck

The awkward thing is that Druid has two really strong decks that will usually beat you. They have aggro tokens and jade. Mulligan to beat one means the other one beats you. Choose wisely.

I'm not saying the deck isn't good, but I'm stuck hopping between ranks 10 and 12 with Elemental Mage. The only decks this consistently beats is pirate warrior (a dying breed), Shamans, Warlocks, and Paladins (that aren't murlocs).

The deck actually works better when you drop the less useful murlocs and non-murlocs. Load up on any random spells which will only keep stat boosting murlocs to draw up every turn.

Oracle, Tidecaller, Bluegill, Bilefin Tidehunter, Oracle, Seer, Warleader, Lookout, and Old Murk-Eye were the only ones I used. 

What game is this from?

This deck has so many awkward and unplayable turns. Twilight Summoner will almost always just lose you the board so I replaced it with Tomb Pillager.

I took out Edwin and added Sir Finley because there isn't enough cheap stuff in the deck to even consistently get him to a 6/6 and the dagger power is near useless.

Dark Iron Skulker is too low value and slow at one copy so replaced it with Shadow Strike to deal with beefy minions. Even Zoo plays Councilman so there's a good target for it in every matchup.

Those are just my initial reactions, but I'm sure after a few more games I'm going to want to replace some other stuff because this deck just has a horrible habit of having a bunch of 4-6 cost cards clogging up your hand.

Forlorn Stalker doesn't have enough targets to be reliably good. I'd definitely replace it with The Black Knight due to all the Twin Emperors running around.

I'd also recommend switching out N'Zoth for a single Gladiator's Longbow. Having a third weapon is good and it actually does something in the deck instead of sitting in your hand all game or having no impact.

I decided to cut 1 Knife Juggler (just one for comboing with Unleash seems fine) and the Stranglethorn Tiger for 2 Freezing Trap. Even without Scientist pulling them for free, it's still an insanely good card. That may just be personal preference though. The other Knife Juggler might become a Huge Toad in the very near future.

Quote from kylistur >>

Why eaglehorn bow without any secrets? Isnt very good?

Too slow, too weak. If you Argus it, it's a 2/2 with taunt, sure it brings a 5/5 but you might be just dead the turn after when you needed a bigger minion to taunt or simply more power right away. Twilight Summoner is a decent choice against heavy control decks but I just don't like it in general. The only match up I would play it over Tomb Pillager is control warrior because of Brawl and even then, you can just play around it.
Might be just me but I think eventually people will play something else.

Edit: Even when you bring it back with N'Zoth, the Corruptor it's bad, when you play N'Zoth you are hoping to get enough power on board to kill your opponent the following turn, 1 attack is just not enough.