Hearthpwn

This is a general control mage deck theorycraft without hero power cards as they are too slow and will get run over by aggro. It has early game tools to survive against aggro as well as a good amount of value generation from watch posts and spell generation. These combined allow to draw through the whole deck and finish the game with Alex and C'thun. 

Alternate card considerations: replace Death's Head Cultist with Venomous Scorpid for worse matchup against aggro but better against control. Because the plan is to get through the whole deck, Mankrik could be good but don't think he makes the cut for this list. Feel free to recommend anything you think I missed.