Hearthpwn

This is the deck I used to defeat Heroic Patchwerk.  The basic idea is of course to stall and the taunts are all about the stall.  Midgame you can usually get plenty of minions on the board and if you have enough cheap taunts, Water Elemental can start freezing the boss until he uses his ability on them.  Alexstraza is in there simply to give you two more turns to live.  The Dancing Swords are intended to cause him Fatigue damage which you can trigger with your Coldlight Oracles as well.  He also seems to take fatigue damage after summoning his replacement weapon.  The Duplicate secrets are for reusing your Mad Scientists although I suspect they can probably be replaced.