This deck is both tempo-oriented but has strong combo potentials with cheap spells churning out 5/5s for Chenvaala or random spells from Mana Cyclone.  You should have no problem putting down a Mana Giant that costs 4-mana or less by Turn 5.  I tried Mountain Giants in earlier versions of this deck but got inconsistent results.  Sometimes it was very strong as my hand was full of random spells from Mana Cyclone, but if I drew it before a big combo turn it often would sit dead in my hand.  I opted for Water Elementals instead as they lead well into Bonfire Elementals and Elemental Allies for additional draw and are overall a more consistent minion to play in this list.

If you're wondering why there's a seemingly random Zephrys, it should be added that you can easily draw through your deck thanks in large part to Elemental Allies along with the Bonfires and Stargazer Luna.  Zephrys can add a nice finishing touch, but do not be too greedy with him.  Play him for tempo if you need to contest the board.  As far as mulligans go, when going first always keep Violet Spellwing, Elemental Allies or any 3 drop.  When going second, the mulligan is pretty much the same but feel free to keep Mana Cyclone with the Coin.  You don't need massive Cyclone turns, even using it for one or two random spells can sometimes change the outcome of the game.

Feel free to drop any feedback and enjoy the deck!