Dobbler said:
I've built several MwnK decks lately, and they simply haven't been as good as I hoped. Its essentially a combo deck...you need MwnK on the table (4 gold investment), you need a reinforcement in hand (another 2-3 gold required to trigger MwnK), and you need a high quality neutral or OOH card to steal. In order to make the combo reliable you have to play Summoning Season to go get MwnK, and you need to play 9-12 reinforcements. By the time you've done all that, you have really watered down you deck against anything that isn't relying on neutrals and OOH stuff. And don't forget MwnK can still be canceled by some of the common cancel effects (He Calls it Thinking, Seasick, To Be A Kraken)
Its always a big swing when you get to steal a high quality card (The Wall, WIldling Horde, etc, etc), but it just isn't a reliable tournament strategy.
That's pretty telling analysis - coming from one of the game's foremost combo players and evaluators.