Low-budget Ragnaros/Executus Hunter Deck (Heroic Mode)

Strategy

On Heroic Mode, the Ragnaros form of this boss is simply too overwhelming to defeat fairly. So this deck's strategy is to kill both the Majordomo Executus and Ragnaros the Firelord forms in the same turn, bypassing the power of Ragnaros and not giving him a chance to affect the game.

Defeating the Majordomo Executus form is a challenge in itself, due to his Hero Power summoning a 2-Mana 3/3 Flamewaker Acolyte every turn. This deck is based around survival against Majordomo, simply limiting his advantage in the early turns, until you are able to gain control of the board. Cards like Quick Shot, Multi-Shot, Hunter's Mark, Eaglehorn Bow, and Kill Command will help to stem the tide of his Hero Power minions in the early turns, to allow you to get to the mid-game period, where you can start to drop a Taunt every turn.

The Taunts in the deck are all included because of how effectively they deal with 3/3 minions, and once you start to get them in play, you will quickly start to see the game tilt back in your favour. From here, your goal is simply to get to Kel'Thuzad, using Tracking if necessary, which will turn your Taunts into an infinite wall that will never get broken. It is important during this time that you do not lower Majordomo Executus' health below 21. The reason for this is that he carries 10 Molten Giants in his deck, meaning by leaving him above the playable threshold for these cards, his hand will quickly fill up with dead cards, leaving him unable to answer your board.

Once you have this wall in place, it is simply a matter of getting Gahz'rilla into play, and then buffing his attack using the various effects like Arcane Shot, Elven Archer, and Wild Pyromancer. Use a Faceless Manipulator on Gahz'rilla if necessary after buffing him to create even more damage. Your eventual goal is to have enough damage on board to burst Majordomo Executus down from 21 health to 0, and then to deal the 60 damage necessary to Ragnaros the Firelord in the same turn.