This deck is from Blizzard’s Off-Meta Spotlight #8, here’s what they had to say about it:
Elemental Mage – 54.2% winrate/120 games
This tempo-style Elemental Mage has lots of great tools to help control the board and overwhelm opponents. It then utilizes the Mage class’ explosive spells to help clear the way for its minions to end the game. However, if opponents happen to survive until the late game, Frost Lich Jaina makes an appearance to help seal the deal.