Hearthpwn

This is a tempo deck that exploits warrior damage cards that enhance your minions.  It uses some of the same cards that previous Blood Warriors type decks have used, but instead of using control/combo elements to build up overwhelming advantage with Arcane Giant, it instead tries to tempo opponents from the start of the game and finish with massive burst damage from hand.

Animated Berserker:  This is a nice tool from KFT that allows you to quickly exploit minion damage effects without burning cards to do it.  It's also a nice turn 1 play to control aggro decks.   It allows us to get immediate value with Acolyte of Pain and Val'kyr Soulclaimer.

Val'kyr Soulclaimer:  This is a nice early game board control tool that lets you go wide and remove threats while still pushing damage.  It's not quite an Imp Gang Boss but it's a decent alternative and since it's usable in Warrior it's actually easier to exploit it's trigger.

Blood Razor:  This card is incredible in this type of deck since it allows triggers to occur turn after turn repeatedly while also controlling the board.  The second swing with it also allows for some great exploits since you don't need to invest mana to get the whirlwind effect.

Grimy Gadgeteer:  This saw some play early with MSOG but then fell out of favor, but I like it in this deck because of the hand burst potential with charge cards.  It's also great with stuff like Acolyte of Pain for additional draw triggers.  It's basically good with pretty much every creature you have in allowing more damage triggers OR just killing your opponent. 

Sudden Genesis:  This was a overlooked card from Un'goro that has a nice home in this deck.  It allows for some crazy burst damage from hand or if necessary generates great value.  You can use this with a wide board before a Battle Rage to draw a ton of cards OR you can use it alongside stuff like Kor'kron Elite or Leeroy Jenkins to do crazy burst damage from your hand.     A dream sequence is Leeroy into Inner Rage into Sudden Genesis hitting your opponent for 16 damage from your hand (or even more if buffed with a Gadgeteer).  If your opponent leaves minions on the board like Kor'kron you can potentially do a lot more all in one turn.

Scourgelord Garrosh:  His ability is obviously relevant in this deck, but his weapon is why he's used here.  He allows you to clear threats in the end game to push those last points of damage through.

 Replacement Cards:

Leeroy Jenkins:  You can use Reckless Rocketeer but it's much worse since you can't use the Sudden Genesis combo with that card.   

Hogger, Doom of Elwynn:  Something like Bonemare might be viable here.

Grommash Hellscream: Reckless Rocketeer is probably the best option

Scourgelord Garrosh:  No real replacement for this but you can supplement empty slots with stuff like Blood To Ichor or Cruel Taskmaster or even Ravaging Ghoul although it's too slow in this type of deck TBH.