Cheap Razorgore the Untamed Priest Deck (Heroic Mode)

Strategy

Priest is a natural fit for this fight, since they have access to so many tools that allow you to deal with the Corrupted Eggs, which are the main problem presented by this fight. Since most of those answers come at higher Mana costs, this deck plays multiple minions such as Crazed Alchemist, Explosive Sheep, and Wild Pyromancer that can help you keep control of the board early.

Once you have reached 4+ Mana, the game becomes heavily in your favour, as you are able to use cards like Mass Dispel to quickly neutralise a large board on your opponent's side, as well as using cards like Shadow Madness, or Cabal Shadow Priest to steal an Egg for yourself, gaining eventual control of a 7/7 minion.

When using Shadow Madness, it is best to try to steal an Egg that has been raised above the 5 Health cap required to hatch, and then simply heal it on your side of the board to gain the 7/7. Alternatively, you can use Power Word: Shield on an Egg with a lower Maximum Health to gain the 7/7 immediately.

The key to this fight is a strong opening hand, and it may take a few attempts to survive the opening turns, but once you have got through this opening period, the fight is overwhelmingly in your favour.