Which was the hardest Deck ever to be played in Standard ?

I had a discussion with a dude on redddit today that made a post stating the OG Grim Patron Deck wasnt as hard to pilot as people make it out to be. Obviously I disagreed with him on that but it really made me think about what deck actually was the HARDEST to pilot. The GP deck had a low winrate at the time even though ( and any player who played hs at the time will agree with me on that )  in the hand of the right player it used to be absolutely devastating. So the deck was really high rewarding, hard to play and even harder to master. I personally might even go as far as saying it could be the hardest out there. Im really not sure though. The other decks high up there would be Miracle rogue and freeze mage I reckon.
As I said Im really not sure though :D ! What do you guys think were/are the hardest decks to play ?

Nomi priest was awful at lower levels and pretty decent at high legend for a while. So that one would be a very difficult deck to master as well. Same goes for test subject priest.

I guess DMH warrior is also up there as it requires a lot of planning ahead and knowing what specific hand you need to go for against every opponent.

As an archetype? I'd go for miracle Rogue. As an individual deck, i don't really remember but could it be Raza Priest?

I found the quest mage very difficult to master

Renolock

Patron probably takes first.

I’d add quest rogue as second (not all of it’s iterations though).

Then APM Priest. Literally the only deck I never tried to learn to play.

Nomi Priest.

Topsy Test subject priest?

Might be a surprise for some, but Cubelock for me. It might be because I played it post-nerf, but I could never get my win rate close to 50%. I often didn't know what to do in the early game, I burned cards from having a full hand all the time, and I had difficulty timing its synergies. That deck takes considerable skill to pilot which I never managed to cultivate. 

DMH Warrior was difficult too. That deck was like the ultimate survival test lol. 

Quote From AliRadicali

Topsy Test subject priest?

That was my thought as well. The deck had a lot fewer ways to survive and stall out the game than other OTK decks imo. Plus the whole APM thing (which is a real barrier especially when faced with Voidlord taunt walls back in the day)

What makes a deck hard? I guess the learning curve for some decks is a bit longer than others, but anyone can learn any deck reasonably quickly. Just play it a bit. 

It depends a lot on the match-up. For example, playing Big Spell Mage vs aggro was easy: mulligan for removal, hope you draw DK Jaina in time. But vs control you had to figure out whether you would be best off taking it to fatigue or not, how many threats is enough to bait out removal, how to pace your own board clears, which cards to dump when your hand got too full etc, while every turn trying to set up for creating a Water Elemental that turn and/or the next. Probably not the hardest deck ever, but the difference in difficulty per match-up was huge.

Any kind of miracle deck is tricky, since you cannot plan your entire turn ahead when you're drawing or generating cards at every step. Rogue is most famous for this of course, but Lyra in Priest and currently Cyclone and Luna in Mage are similar.

I would definitely go with APM priest too, even though it was actually a meme deck. This deck needed a cheat sheet while learning it and it was so fun when you could pull of the combo.

PS: I know the OP didn't ask, but I play wild mostly, so I felt like talking a bit about that too. In that context, I would confidently say Kingsbane Mill Rogue (before the leeching poison nerf), or any mill rogue for that matter. In that meta you had to deal with pre-nerf Even shamans, Odd paladins (with level-up) and odd rogues. So hard to survive (when you could die by turn 5 some times), but also so rewarding when you could have built a large weapon and hammered the face while clearing boards with vanish etc. Moreover, it kept Big Priest, Reno Lock, Jade and Togwaggle Druid in check. You could say that it was a tier 2 deck, which in the right hands was a tier S deck.

Does the deck have to competitive? I made the below deck as a "challenge" a while ago and it was super difficult to pull off but really fun when you did. It was a guaranteed win if you could (1) get below 10 health without dying, (2) get your opponent down to at most 25 health and (3) have exactly one minion and no other cards left in your deck. Note this deck was standard after the MSG release, and actually became slightly easier (modified for standard) with release of Baleful Banker in WW, because you no longer needed Emperor Thaurissan and didn't have to worry about leaving a minion in your deck.

Besides APM priest (that I cannot play at all because my internet connection is slow and I can't get enough actions per minute to play it), the deck I truly never mastered is pirate warrior in wild. I know that it's stupid, but I wasn't able to smorc my way out.

However, I never get the chance to play old school patron warrior, and that makes me sad sometimes. I think that Wild should be more wilder. I would love to Hall of Fame the Warsong Commander to "your minion with 3 or less attack have charge" or something like that.

Control Shaman.

Patron warrior (prior to Warsong Commander nerf) and now egg/enrage warrior is probably the hardest to play in their time.

- Its a combo deck that relies on very specific cards, but with no strict requirement for the win (you can still do very well with Warsong Commander + Frothing Berserker) so players have to both rely on information currently at hand and possible draws in the future. Not exactly easy stuff

- The deck at its best requires the player to understand the amount of damage possible currently, and what specific card can give them lethal in the next few turns. So do you swing your Death's Bite for that 4 damage to face, or hold on for patron? Do you swing now, or later? you also have to account for ooze, which can easily scupper your plans. What if there are multiple taunts? etc.

- At that time, there were some disruption cards that can easily block patron warrior like Loatheb. Also, the deck didn't exactly have the best board clears at that time so it cannot simply ignore board like how the current egg warrior has with armorsmith + risky skipper.

- Unlike other combo decks, patron and egg warrior's combo rely on damaging their own minions, so misplays are honestly very common.

- Like APM priest, this deck plays lots of cards for the win. Unlike APM priest, the damage output is finite. So you can easily dump all your cards with no straight forward guarantee for the win, and even if you do, one mistake is all it takes to complete belly up the game. APM priest has a specific sequence which means its easily memorized, patron/egg warrior does not.

Have a look into youtube. One of the notable matches I can remember was lifecoach vs trump (yes its more well known for that roping meme) Undoubtedly there are better matches, but I can't recall the exact names of the players.

Rastakhan's Rumble's Exodia Mage was quite challenging

I didnt know that this subject was debatle. I guess not many ppl played DMH Warrior.

Definitely APM priest even if its was only for yhe mechanical part

Maybe back in it’s standard days, but it’s ridiculously easy now in Wild.