Deck originally created by HotokeTaro.

Hero Power: Wyrm Bolt

Signature Treasure: Embercaster

I ended up getting 12-0 with this deck with passives Arcane Flux and Khadgar's Scrying Orb. Generally speaking, you are looking for either something that you can combo with the Discover mechanic or spell buffs such as spell damage or cost reduction when it comes to the signature treasures. 

Your card bucket choices should depend mostly on your passives, if you end up getting Arcane Flux, try to draft as many cheap Arcane spells as you can to get the most value from them all as you will almost generate an infinite amount of spells by saving a few Arcane spells to cast each turn. For some other mechanics, such as Staking A Claim, you may end up going more minion-based to allow you to buff your minions when playing one of the many mages discovers spells.