Hearthpwn

• • Power Word: Shield : Draw and helps for better trades
  • Twilight Whelp : Best 1 mana drop for dragon decks
  • Mind Blast : Finisher!!!
  • Shadow Word: Death : High dmg trades
  • Holy Nova : Clear
  • Entomb : Exile a strong card from his play
  • Prophet Velen : Big creature, Double dmg, Double heals... Just this...
  • Netherspite Historian : Best 2 mana drop for dragon deck
  • Blackwing Technician : Strong 3 mana drop for good trades
  • Barnes : 4 mana two minions on board with a chance of a good ability triggered
  • Twilight Guardian : Strong taunt for aggro decks
  • Azure Drake : Draw, Dragon
  • Blackwing Corruptor : Good trades
  • Book Wyrm : Good trades
  • Emperor Thaurissan : Lower mana costs
  • Justicar Trueheart : More survivability
  • Chillmaw : Taunt, clear
  • Alexstrasza : Aggresive or defensive
  • Malygos : +5 dmg
  • Ysera : Strongest Dragon
  • Deathwing, Dragonlord : Party with Dragons

The whole deck is full of combos and synergies, as it is a Dragon deck... The main idea of this deck, is to play like a normal Dragon deck and wait for the combo cards to finish him with Mind Blasts... The combo cards are Mind Blast, Prophet Velen, Barnes, Emperor Thaurissan, Alexstrasza, Malygos and Deathwing, Dragonlord... There are many ways to finish him... So that means that the deck doesn't depends on 1-3 cards to win... 

The combos has a lot of damage to also kill a warrior with armor!!! So lets see the combos:

1. 20 dmg/8-10 mana: Prophet Velen + Mind Blast x2 (with Emperor Thaurissan reduction just for one card at least)
2. 20 dmg/10 mana: Malygos + Mind Blast x2 (with Emperor Thaurissan reduction once on each card)

 Now lets improve those combos... 

• No.1 and No.2 can be better if you play before Alexstrasza and put his life to 15...
• No.2 combo can be better if you are holding Malygos + Mind Blast x2 and play Deathwing, Dragonlord... That means you'll put on board Malygos for free, if your opponent kills him, or you still have 12 dmg on board :D... Much better if you got also a Power Word: Death, deal 12 dmg first with Deathwing, Dragonlord, then kill him with Power Word: Death (Malygos) will drop on board) and play Mind Blast x2... That means...........32 dmg in one turn!!! And no need Emperor Thaurissan!!!
• The best is to have on board Malygos and play next turn Prophet Velen + Mind Blast x2... Its 40 f@#!ing dmg!!!

Some important Tips:

• Keep always The Coin for the combos or spend it only on emergency against aggro decks
• Deck is so flexible and no need to count only on Emperor Thaurissan for the combos like Mage OTK Decks
• Bait your opponent to spend removals on wrong targets to keep a combo alive (like sacrifices)
• Most people will think that will be a simple Dragon Deck and you'll more easier OTK them
• Keep the Board Control with good trades and try give him 10 dmg to prepare a safer OTK
• With Netherspite Historian get dragons like Twilight Guardian, Book Wyrm or any other Legendary depending on opponent class/deck...

For every opponent:

• Netherspite Historian
• Twilight Guardian
• Blackwing Technician
• Twilight Whelp
• Power Word: Shield

For Paladins/Shamans/Warlock

• Can keep Holy Nova for clear

For Shamans/Druids

• Can keep Power Word: Death for early big threats