Hearthpwn

   General Information:

This is a Beast Midrange Hunter deck. That means it has many beast synergistic cards, which can be divided in cards that produce beasts and cards that build up on those beasts.

Cards that 'produce' beasts are: Webspinner, Snake Trap, Haunted Creeper, King's Elekk, Animal Companion,Unleash the Hounds and Savannah Highmane (Piloted Shredder could count also).

Cards that build up on those beast are: Kill Command, Houndmaster and Ram Wrangler. With Beast(s) on the board, those cards can give you immense value and are therefore very important for this deck.

   Card Replacements:  

Gladiator's Longbow: You basically can replace it with any card which is played in other Midrange Hunter decks. I personally would replace it with another Sludge Belcher or a second Piloted Shredder.

King's Elekk: Another trap is a nice replacement for this card. Explosive Trap or Bear Trap are possibilities, either for board clear against Aggro Decks or simply for beast production.Quick Shot could be another replacement.

Flare: I just play this cards in response to the Paladin-Meta right now. I highly recommend playing this card until the meta shifts again. Quick Shot could be a nice replacement for this card.

Snake Trap: This card is pretty important for the beast production in this deck. Taking this card out would make it much worse, but if you really want to replace it, if you don't have it for example, you should concider using Explosive Trap or Bear Trap, just for having two different secrets in your deck, which makes Mad Scientist way more efficient.

Loatheb: A second Sludge Belcher.

Dr. Boom: Replacing Dr. Balanced isn'nt a good idea. It often either turns the game to your advantage or if you are already winning, it helps getting complete control of the board. If you don't have this card, you could replace it with another high value lategame drop like Ragnaros the Firelord. Although I think crafting Dr. Balanced is  worth the dust in any situation.