This is my first deck on here :)
The strategy is to Mulligan for Animated Armor. Freeze his board and put up taunts until you draw it. Slitherspear keeps thinking he has lethal but in reality is only dealing 1 damage per attack (its pretty satisfying xD)
once he's on the board (never play two at once) you want to play Antique Healbot and Ice Barrier to heal the 8 damage he deals you each turn. Use your Blizzards Polymorphs and Frost Novas to hold him off too
Animated Armor might die but if he does you have an extra one in your deck/hand. If both die (which is pretty rare) or you cant find the other one then just concede, and try again.
Keep hitting him each turn with your healbots and animated armor, until you can finish him off with fireballs and/or minions.
If you need any help just message me :)