Hearthpwn

Warrior was hardest followed by paladin all others I got on the first attempt.

Paladin >>>>>>>>>> Climb Everest >>>>>>>>>> run Crysis in a 486 >>>>>>>> all others.

For some reason I struggled a lot with Shaman... Warrior and Paladin where a breeze tho.

I finally did it but Shaman screwed me up so much. It felt like no matter what I did, Thrall DK and Evolve were my bottom 5 cards, and those 1/1's don't get you very far. And I'm not convinced that the Lich King doesn't run 5 Blizzards. But whatever, got Arthas now!

Hunter was the hardest for me. Don't remember the final deck, but I do remember I ended up using something like 6 minions in an ungodly mess of a Reno deck that generated minions through a lot of spells. Paladin... I just resorted to the KT/Taunt exploit. Warrior wasn't that hard as I played a lot of Patron Warrior back in the day, so I pretty much applied that concept to a more control version of the deck. Mage was actually pretty easy.

Hunter was the one that took me the most tries, but then I didn't netdeck anything and tried multiple ways to beat it (Barnes-Yshaarj, no minions etc.) finally beat him with Molten Giants and Scavenging Hyenas. 

Warrior was easy, control warrior with Kel'thuzad.

Paladin took a couple of gos with a super aggressive murloc deck with lots of buffs (killed him on turn 5).

This was for sure a super fun challenge though, and I especially enjoyed thinking for myself how to beat him with each class. Beating him after turn 7 was far more satisfying than smorcing him down with murlocs though. I came within a few points of damage of beating him with a Deathstalker Rexxar no minions control deck which was super fun.

Beating him with Mage without Counterspelling The True King was the most satisfying though.

17 people said Priest, and 9 people said Druid at the time of this comment. I really want to hear how those people justify their votes lol

From Hardest to easiest for me

Warrior > Shaman > Paladin > Hunter > everything else with priest being the easiest

Warrior was by far the hardest.. I ran the grim patron deck and man you literally cannot make any mistakes, and you have to mulligan very well and hope he doesn't have blizzards. lich kings turn 6-8 was the hardest phase. Took me about 3 hours non-stop till i finally beat him. Was the most satisfying moment ever!

Shaman, i probably made it harder than it should be. I ran the standard evolve shaman deck because I didn't really want to craft the extra murloc cards. Shaman was all about high rolls. Hope he doesn't have blizzard on his turn 6. Hope your devolve + lightning storm kills off his minions during frostmourne phase. Hope your doppelganger + evolve combo is good and that you have bloodlust to finish him off. Heaps and heaps of resets took me about 1 hr

Paladin - Similar all about patience and RNG. Basically I kept restarting till i got tidehunter + rockpool + warleader. also an hour.

Everything else was fine didn't have too much trouble.

My vote is Mage, though I should add that I used the bug with Warrior to get past it.

Most were doable after all. Jade Druid, Silence Priest and ... Go Murlocs! Was worried about Rogue as I never play that class but did well ... with Murlocs.

I had a rather quick Pally win with incredible draw and RNG luck (e.g. getting the guy that doubles your end of turn effects from his deathrattle creature and was able to combo with Ragnaros...- yup, no Murlocs here)). I think that could have gotten nasty...

Couldn´t do Warrior without the exploit.

Daedalos1337, I applaud you.

EZMODE
Druid
Priest 

DONE IN A FEW TRIES
Warlock
Shaman
Hunter
Rogue

CHALLENGE
Mage
Paladin

STILL FUCKING TRYING!!!
Warrior

I'm fighting him with basic cards... And some other cards with crafting and i can clearly say that alarm-o bot warrior is not that hard, it took nearly 2 hours and 5+ tries (not counting restarts to get the alarm-o bot + stub gastropd combo)... I also troubled with mage with same reason (kabal lackey + mana bind combo). Imo, warlock is the hardest ( i had f**kton of restarts and still no luck) if playing with basic cards (and with some other cards)

I had considerably more problems with mage than anything else. It  wasn't much fun either, too much reliance on a good mulligan.

Paladin of course, took me more than twice time of rest classes combined. Mage/hunter easily can be cheesed with molten giants, warrior with KT. Rest were pretty much first/second-try. Overall took 4-5hours.

I counter spell with mage at  first turn frim there EZ money

With lock I just went murloc with a lot of duplicates and some singleton.. given that you start with some cards in hand, you take a bit less damage, as they count duplicates still in deck. I got a hit of around 24 damages, and then just won without a single HP lost anymore... after all I've done the same with Jaina, who starts at only 1HP. Yeah, that's how much murlocs are strong there

Quote from Clavix >>

Warrior. I can not even imagine how this may work without the KT-Glitch. :-/

paladin and hunter took me dozens of tries/restarts, shaman was also tough. the rest went rather well, all under 5 attempts