Hearthpwn

I was inspired by Spark's Pyromancer deck and wanted to counter the heavy mech-mage play post Undertaker nerf.

The basics are simple. Try to mulligan for Snipe/Mad Scientist/Eaglehorn Bow. Snipe destroys just about every core mech card aside from the occasional Mechanical Yeti. Save Hunters Mark for Wild Pyromancer or just use it freely, there's plenty of cards in the deck to save you until you can drop a Savannah Hyena or anything larger. Save The Black Knight for Taunts, especially other Sludge Belchers. Try the clear the field by the time you drop Ragnaros. Healbot can keep you on the offensive and alive late game. Faceless Manipulator is your freebie card, copy what you see fit or for a double Ragnaros.

As for replacements, start with 1x Savannah Hyena or 1x Azure Drake as to your liking. You could possibly take out the Legendary cards for Knife Juggler + Snake Trap + Unleash the Hounds if you're on a budget.