Hearthpwn

Played this from Plat 9 to legend (60w-20l).

The key to this deck is knowing what your win condition is for each matchup and being flexible.

The strengths of this deck are its healing, AOE and reactive minions vs tempo/agro/burn decks and its consistent pressure, high stated minions and Galakrond hero power vs slower controly decks.

Although this is the deck i used, here are some changes I would consider if I had the cards; Lord Barov, Rokara, Blademaster Samuro, Moonfang, Playmaker, Stage Dive. the cardsIi would be replacing are Warsong Outrider, Town Crier, Ramming Speed and maybe Siamat.

Mulligan

Top keeps: Imprisoned Gan'arg, Ritual Chopper, Zephrys, Kargath Bladefist.

Good keeps: Athletic Studies, Town Crier, Awaken, Warmaul Challenger, Devoted Maniac, Restless Mummy.

Good keeps vs aggressive tempo decks: Warpath, Rancor, Zilliax, Reno Jackson.

Conditional keeps: Overlord Runthak (with 2 other early good plays), Brawl (vs Paladin, Demon Hunter, Druid and Warlock)

Never keep: Conditioning, Scion of Ruin (unless with 2 other invoke cards), Kronx Dragonhoof or any 7+ cost cards

Strategy

in most matchups you just want to survive early aggression and out-tempo your opponent with buffed minions in later turns.

vs Rogue biggest thing you will want is zephrys for weapon removal

vs Priest and other control decks your objective is to grind them out by holding your mid range  minions and making them into bigger threats and getting value off of conditioning, Galakrond, Runthak and Akali. very important to not overcommit resources into their aoe clears.