Hearthpwn

-Dragon: Cleared him easily on first attempt with my rogue run and I figured he is easy enough compared to the others, but I failed with my hunter as it was a small beasts deck and his breathe is just too much to handle. Do not pop more than 2 chests as a maximum because 3 dmg continuously is just too much if you ever want to have a board. His deck is a dragon priest deck.

-Darkness: Cleared him first attempt with my paladin through fatigue, smart decisions and good counter. Basically I had some aldors and humility to control the early darkness, lots of healing and the RECRUIT treasure. He is not an easy fight at all and it is all about board control and patience, not a race. His deck is mainly priest (pains, deaths, psychic scream, mind control, entomb).

-King Togwaggle: Another ridiculously hard encounter mainly based on RNG, he gets any good treasure early on and it is over for you. Failed to beat him on two attempts.

-Azari the Devourer: This is purely a dmg race and early board control, I beat him on the first attempt with a greedy shaman deck. I basically kept my high cost cards (which cost 5 due to treasure) and took control of the board at around turn 6 and never gave it up. His deck is made out of demons mainly.

-Xol the Unscathed: A discard warlock hero with a powerful hero power that either deals dmg to all your board, executes all dmged, mind control at random, shuffle back into your deck, assassinate, freeze, and probably many others. I beat her with my warrior on my first attempt which was an enrage warrior with whirlwind effects which made me discard lots of her hand by targetting her howlfiends (even got her to discard the quest portal), and evnetually with loads armor (and Justicar) out-valued her with Geosculptor Yip into fatigue.

-Success came from focusing on enrage loot and armor gain (Berserker, Everybody Hurts & Armor).

-Treasure Gathered: draw 2 extra cards on turn 1, boom bot box, play 3 random secrets on turn 1, adapt minion X times.

-Was easy to be consistent and reach the 6th or 7th boss (4-5 runs). Lost twice to king Togwaggle before going into a last boss fight with the Xol and got her from first attempt.

-MVP Cards: Reckless Fury, Geosculptor Yip 

-Success came from focusing on elementals purely and battlecry

-Treasure Gathered: +5 cost minions cost 5, draw 2 extra cards on turn 1, double health, enemy minions cost 1 more.

-One of the hardest decks and I struggled with it even at low level fights but once you get going it becomes good (6-7 runs). Only one last boss fight which was Azari and got him from first try thanks to Kalimos.

-MVP Cards: Murmuring Elemental, Kalimos Primal Lord

-Success came from focusing on picking assassination spells and thieve cards (Assassin & Thief).

-Treasure Gathered: spell power +3, play 3 random secrets on turn 1, icewall, adapt minion X times

-Probably my easiest and fastest run without any struggle (1 run and done). Basically I had lots of spells that I can just burn the enemy with before they even react. At later stages a big Edwin or Questing Adventurer with conceal seals into adapt 6 times seals the deal. Last boss was the Dragon and I beat him with only killing 1 chest, getting the draw 3 cards that will cost 0 into a Questing Adventurer and it was over.

-MVP Cards: Edwin Vancleef, Questing Adventurer, Eviscerate, Backstab, Razorpetal, Sinister Strike

-Success came from focusing on healing and board control, later on switched to greed legendaries with Recruits 3 treasure (Healing, Legendary & Justice)

-Treasure Gathered: minions have +1/+1 (even silver hand recruits summoned!), draw 2 extra cards on turn 1, recruits 3 minions, Wish

-I was never at risk of dying through the loads of healing I have, early board control thanks to 2/2 silver hand recruits. Ending up with huge legendaries (Lich King, Curator, Tirion) to finish it off (1 run and done). Last boss fight was The Darkness, had to go all through to fatigue as I controlled his damage with healing, Humility and Aldor Peacekeepers.

-MVP Cards: benevolant djinn, wickerflame burnbristle, aldor peacekeeper, humility

-Success came from early aggressive cheap beats and late game deathrattle with N'zoth. DK Rexxar is actually not a very good pick until the last fight for value (Wee Beasts & Deathrattle).

-Treasure Gathered: double health, archmage staff, double health, silence and destroy all enemy minions.

-At first I thought I should be playing like the other classes and going for late game loot but as with ladder hunter sucks at control  and hence I lost my first run, your aim is just to HUNT THEM DOWN. So building for the 2nd run I reached the last boss which was the Dragon but since I had all early game minions his breathe just went out of control and wiped my board, although I had 200 hp but I could not race him. Final and 3rd run I learned from my mistakes and built the deck as described above. Final boss fight was King Togwagle and he was fairly easy with me sitting at 200 hp and hitting him for 2 each round. I made him build a weak board of seven minions and I sat back, at the right time I silenced and wiped his board and switched to the DK for value and end game.

-Success came from playing similar to a big druid thanks to the 5 mana cheat treasure (STOMP).

-Treasure Gathered: extra mana crystal on turn 1, 5+ cost minions 5, discover and equip a legendary weapon, double health

-Thanks to druid's ramp and the treasure you can literally STOMP the enemy before they react (1 run and done). The last boss was Xol and as always you try to make her complete the quest then force discard the portal and it is a fairly easy fight. On all discovers I always found the Paladin weapon which is insane on turn 1, note that Druids of the Claw do not benefit from the buff and go back to 4/4 charge or 4/6 taunt.

-MVP Cards: Y'Shaarj Rage Unbound, Ysera, Lich King

-Success came from striking a balance between late game demons (Malganis, Doomguard, Voidlord and early game swarm minions like knife juggler into implosion. Also there is no need to aggressively tap as with Ladder because you have a very small deck at the start (Swarm & Dire Demons).

-Treasure Gathered: play 3 random secrets on turn 1, spell damage +3 (insane with bolt and implosion), the candle, WISH

-Played pretty much like a zoo swarm deck until the last boss which was Azari which was fitting that I faced him as Gul'dan (1 run and done). I kept the Wish and DK in opening hands because they are my win condition. I survived his early board with hellfires and didn't tap unless I felt I had bad quality cards in hand. I only needed DK to finish him off.

-MVP Cards: Knife Juggler, Implosion, Bloodreaver Gul'dan, Mal'ganis.

-Success came from going pure elemental build with Frostlich Jaina to grind out any boss no matter what. 

-Treasure Gathered: double health, archmage staff, justicar ring, extra mana crystal on turn 1.

-I had success with Highlander (Unique loot) to get to the last boss 5 times but not enough sustain and power to finish the encounter. So on my 6th and final run I decided to change strategy and go with sustain and value, hence the Elemental loot.

-MVP Cards: Frostlich Jaina, Blizzard, Dragon's Fury

-Success came from Unique loot (Highlander).

-Treasure Gathered: icewall, 3 secrets played on turn 1, justicar ring, bag of coins.

-Priest is another class in my opinion that struggles in early bosses because of weak base deck and minions. I have lost to Ixlid Fungal Lord because I had no early board although I hard mulligan but by turn 3 his poison one shot me. Dragon Priest decks are very clunky and slow to work. Eventually on my 4th and final run I had the chance to draft a Highlander deck, needless to say it works just like in ladder play. 

-MVP Cards: Shadowreaper Anduin, Prophet Velen, Lyra, Kazakus, Raza the Unchained.