The 6th of March represents a new beginning of Hearthstone eSports with the new Specialist format. If you are not familiar with this format and how it works, take a look at my post explaining it. It is a bit too early to judge how will this format affect new tournament, but let's see how the 1st week played out
The first statistic isn't that surprising, Hunter is dominant for a long time and it seems that it will stay on the top at least until Deathstalker Rexxar rotates out of the standard format because of how flexible this card is and its ability to fit in any kind of Hunter deck. The least picked class is Shaman, with only 10 players bringing him in the tournament. Shaman is definitely the weakest class for quite some time and having only Even Shaman as a tier 2-3 deck isn't enough to see him picked in the 1st week.
Midrange and Deathrattle Hunters are the most popular (over 50% of the 1st-week winners), which is in line with what is seen on the ladder. These decks have the least bad match-ups and are easily tech-ed to have a decent chance in those few match-ups that they need a little help.
Midrange Hunter currently has one of the fastest early games and with Master's Call and Dire Frenzy hardly run out of steam and with DK Rexxar they can sustain the pressure throughout the whole game. Control/Wall Priest and Odd Warrior are best to fight off the early aggression and if they successfully stabilize the board and take control of it they will most likely have a winning game in this match-up although this is not that easy to accomplish.
Deathrattle Hunter, on the other hand, has a pretty good time versus those slow control decks with their sticky high-value minions and dominance in the late game with Kathrena Winterwisp and of course also with DK Rexxar.
It is very hard to come prepared for both of these Hunter archetypes and that's why we see so many of them in the tournament.
Warlocks and Priests
Cubelock is the strongest pick for Warlocks, Zoolock didn't see much success. The biggest problem for Cubelock in the Specialist format is that it gets beaten by techs a bit too much, with oozes to be exact, because of the deck heavily depends on the Skull of the Man'ari. Other weakness of the deck is silence on Voidlords and Cube, but that can at least be avoided with strategic play.
Warlocks best match-ups are slower deck like Control Priest, Big Spell Mage, and Odd Warrior but if they are fortuned enough that Skull of the Man'ari sticks for a turn or two, they will beat even faster match-ups suck as Midrange Hunter and Odd Paladin.
Priest best performing deck was Control, with the ability to clear aggressive board pressures of Hunters and Paladins and bursting slower decks with Alexstrasza and Mind Blasts. Priests minions are well suited for fighting for the board presence and combos like Twilight Acolyte into Cabal Shadow Priest can snatch high-value targets and swing the tempo in the late game.
Control Priest usually struggles versus Odd Warrior because they can exceed max HP thresholds, sometimes even too much so that burst gameplan from Priest becomes obsolete. Luckily in this format Priest can come prepared with Archbishop Benedictus and can create a new win condition of going into fatigue in this match-up.
Struggles of Warrior and Paladin
Both, Warrior and Paladin have the same problem. Their strongest archetype is Odd-based, which within itself is a big restriction and finding a good tech for all possible match-ups becomes way harder.
Odd Warrior is strong against the prevalent Midrange Hunter but going versus Control decks it seems that it finds it hard to adapt. Best tech for them in these situations is the Quest card Fire Plume's Heart although decks like Deathrattle Hunter and Cubelock will always present huge threats and it will be hard to play the quest reward and lose the ability to gain armor for the rest of the game.
Odd Paladin had a decent win-rate of 54% and that makes sense since the core of this deck is really strong and it has the strongest hero power in the game, but again the same problem it has is to adapt to weaker match-ups. They depend too much on the luck of the draw to stay relevant versus Midrange Hunter early push but perform really well versus other aggressive decks. Another problem is that they have a hard time in Control match-up and with so many Priests and Warlocks it is hard for Paladins to progress through the tournament.
The Specialist Format After Rotation
Rotation of playable sets will come soon, most likely around 15-20th of April. Until then we will probably see Hunter dominating tournament scene, not only because of his power level but also because these tournaments are open qualifiers and any player is eligible to participate. Many players don't have too big of collections and Hunter decks, especially the Midrange deck is very cheap to craft considering how strong it is and pretty much straight-forward to play.
After rotation Hunter will lose almost every top tier cards that are currently in all Hunter decks, most notably Deathstalker Rexxar. This will definitely lower his flexibility and lower its potential for infinite value game plans.
Also, there will be no Odd and Even decks since Blizzard decided to rotate Genn and Baku earlier than normal. And honestly, that is a good choice because it makes meta a stale a bit too much, and finally, we won't see that pesky Odd Paladin anymore.
I guess that after rotation top 3 classes might be Priest, Warlock, and Mage because they have got so many new tools to work with in past expansions but couldn't really use them because of the state of the meta. Of course, this depends on what will come in the next expansion.
Thank you for reading!