When facing a Warlock, many players ask before setting up there plays: is this Handlock or Zoo? This question presents itself similarly if a player were to face a Rogue: is this Miracle, Aggro, or Tempo? Knowing what deck your opponent is playing is crucial to any Hearthstone game as you prepare for what moves your opponent will make. There are certain "tells" that signal what your opponent's deck might be. A tell is a term used in poker to determine the strength of your opponent's hands based on the person's actions. The same concept can be applied in Hearthstone, but instead of assuming the strength of the deck, we can use the concept to try and figure out what deck the opponent specifically has from their opening plays.
Note: You may notice that Shaman is missing from the table of contents. This is because most Shaman decks follow the same build.
Warlock Handlock and Zoo are the signature decks of the meta with some Murlocs still lurking about. Warlock is a good place to start discussing tells because they are normally fairly straightforward.
MulliganCheck to see if the opponent has mulligan his entire hand or kept one or two cards. If the Warlock kept most of his hand, it might suggest Zoo; if the latter, it could be Handlock since it is rare to get the perfect card combination in the starting hand. This pattern is often seen because Zoo has much more redundancy than Handlock. While not an accurate tell, it does give valuable information before the game even starts on sequencing your plays.
Coin + Knife JugglerThis is a very common play for Zoo and Murloc. While this does not really specify which deck is which, this should signal that the Warlock is aggressive and a lot of stuff will be coming your way in turn two and three.
Turn one - Nothing, Turn Two - Hero PowerThere is no greater feeling of disappointment when the opposing Warlock does nothing in turn one and taps the second. This is the most common tell to determine if your opponent is using Handlock. Handlocks' rarely have turn one or two plays and so they will simply tap to grow their card advantage or get ready their Mountain Giants.
General MurlocsWhile some more aggressive Zoo decks may play Bluegill Warrior, any murloc usually signals the potential for more. Once you identify this deck you need to respect the possibility of big burst coming from Old Murk Eye or Murloc Warleader. You should also keep their board clear to avoid Health buffs out pacing your board clears.
Void WalkerThis annoying taunt minion can be found in all decks, yes including Handlock. There have been variations of Handlock that use Void Walker to try and deceive opponents thinking that there deck is Zoo. He is mostly featured in Zoo decks but if he comes out alone and is not backed up on turn two then keep the possibility of Handlock open.
For a while, Miracle Rogues has been prevalent in ladder much to the dismay of most players. The deck has become so popular that many pro-players just out-right assume that it's Miracle Rogue when they see Valeera's face. What is interesting, however, is that the early tells a Miracle Rogue might use is similar to tells that a Tempo Rogue might use.
Tempo Rogues are filled with Knife Jugglers, Argent Squires, and Azure Drakes to maintain board control and finish with strong burst and Cold Blooded minions. Even though this deck is out-of-flavor recently, it's still a viable deck that many players use on ladder.
Aggro Rogues have been popping up recently to counter their Miracle counterparts.
MulliganIf you see the opponent mulligan their whole hand or most of their hand, chances are they are playing Miracle. Tempo and Aggro Rogue tend to have many one-cost or two-cost minions so there is room for a minion to slip into the starting hands. If your opponent is second and still mulligans their entire hand, there is a great chance that it is Miracle since the second turn gives you an extra card to mulligan.
Backstab or Coin + SI-7 AgentThese plays suck to play against but two of the many reasons why Rogue is infamous in terms of tempo control. Backstab and SI-7 Agent are core of any Rogue deck so these tells are not the sure-way of knowing what Rogue deck it is.
Turn Two WeaponThis is the most common early play for Miracle Rogue since the deck rarely have any early plays besides Backstabbing a minion, but this tell shouldn't 100% assure you that the Rogue you are facing is Miracle Rogue. The reason why a Tempo Rogue player would weapon up in turn two because it's easy to clog your hand with unusable spells in the early stage such as Deadly Poison, Blade Furry, Cold Blood, etc. While the chances of a Tempo Rogue having a bad hand is low, you should still consider the possibility of Tempo Rogue.
Argent Squire, Knife Juggler, Leper Gnome, it is obvious that they are not playing Miracle. These cards lean towards Tempo or other aggressive decks.
There are three Druid decks that are showing up in ladder: Ramp, Midrange, and Token. Midrange I believe, is the most popular of the three in Ladder, but the other two are pretty good in the current Meta and are also relevant in ladder as well.
Turn Two Hero PowerA Druid using their Hero Power is not an accurate tell of what the Druid might be playing. Druid usually has many big minions in their decks and will sometime clog his hand.
Coin + Wild Growth/ Turn Two Wild GrowthWild Growth is one of the signature spells of the Ramp deck but is also run in some Midrange builds. This spell cannot accurately say what deck the opposing druid is using, however, it does usually cut Token out of the equation.
Power of the Wild on turn two to maintain board control in order to set up for their mid-game dominance.
Any One DropToken decks may run Argent Squires or Leper Gnomes to pressure their opponent early and set up their Force of Nature / Savage Roar combo. Any one drop should be a clear signal pointing to Token Druid.
While Warrior is a decent counter to Miracle Rogue, Warrior decks are declining due to their lack of mas removal and fall to many Druid and Shaman decks. Still, a few still play the Warrior class with its two variations: Control Warrior and Face Warrior.
Any One DropA sure-sign that the opposing Warrior is Face Warrior. Control Warriors generally do not have any need for any of the one-cost minions. In addition, one-cost minions lean toward aggressive decks so an opposing Warrior summoning such minion is a sign of an aggressive deck.
Fiery War Axe: Hold or Attack Face?Fiery War Axe is one of the signature weapons of Warrior, but the important tell is if the opponent attacks your face. Control Warriors tend to save their Fiery War Axes to maintain board control, but Face Warrior aim to deal the maximum amount of damage. If you see the opposing Warrior holding their Fiery War Axe, there is a good chance that it is Control Warrior.
Armorsmith or Armor UpOne of the signature cards of Control Warrior. Should be no surprise that when this is summoned, it should signal that the game is going to be a long one. The same goes for an early use of the Hero Power: such an early defensive move points clearly to Control.
Coin + Frothing BerserkerWhile Frothing Berserker is in both Control and Face Warrior, coining a Frothing Berserker usually implies aggressive behavior. This shouldn't be a 100% giveaway to Face Warrior though since some Control Warriors players coin Frothing Berserker to gain board control.
Aggro Paladin has been making a return in ladder in response to the Hunter nerfs. While not as fast as the pre-UTH nerf Hunter, the Paladin comes in a close second. That said, there are still a few Control Paladins battling on the ladder.
Any One DropWhether it's Leper Gnome or Argent Squire, these are all signs of an Aggro Paladin.
Coin +Knife JugglerA very common start for Aggro Paladin, much like Warlock Zoo and Murloc since Paladins are a swarm style aggro deck.
SecretsEver since the Secret tune by Blizzard, making them unable to activate on your turn, Secrets are primarily used in Aggro Paladin. Noble Sacrifice is the most commonly used secret so assume that is their play if you see a Secret.
No Plays or Early Hero PowerThe lack of any aggressive opening is indicative of a Control Paladin. All of the Aggro builds have enough low drops that a lack of plays in the early game almost certainly points to a control build.
Token, Tempo, Secret, and Freeze Mage are also making a comeback with great matchups against Miracle Rogue and Shaman.
Arcane Missles / Mirror ImageWhile these cheap spells can be found in all Mage decks, these two lean more towards Token or Secret decks. Both decks tend to run Archmage Antonidas and these spells are used to activate Archmage Antonidas's effect quickly in the late game. While not a sure tell for Token or Secret decks, the probability is high.
Turn Two Hero PowerIf a Mage does nothing on turn one and use the Hero Power on turn two, then the Mage is probably using a Freeze build. Even with Mulligan, the Mage should have at least a turn one or turn two minion if they are using a Tempo, Secret, or Token Mage.
Turn Two - Coin Kirin Tor Mage to SecretA sure tell that the opposing Mage is using a Secret deck. This is one of the most efficient plays in the deck.
Arcane Intellect can be used in the Token deck to get Violet Teacher much faster and to feed her with spells so that she may start producing tokens. It is also used in Secret and Freeze Control decks to generate card advantage.
Amani Berserker is cheap and very effective threat in this Mage deck.
While Amaz Priest and Velen Priest are probably the only two kinds of viable Priest decks in the ladder, it is quite hard to differentiate between the two in the early game since both decks utilize similar tells.
Both decks run Circle of Healing, Northshire Cleric, Wild Pyromancer, Thoughtsteal, etc. The only significant tells that can be used is during the later stages of the game.
Velen Priest utilize Cabal Shadow Priest, it is not currently used in Amaz's build of the deck.
Due to the Unleash the Hounds nerf, Hunter users have dropped dramatically, but some still linger on ladder. Face Hunter and Midrange Hunter are what most Hunters use nowadays.
Arcane Shot to the FaceA sure tell that the opposing Hunter is Face Hunter. Arcane Shot is a efficient removal spell and it being used to deal direct damage is a clear indicator of the Hunter's intention for a short game.
Leper Gnome/ Bluegill Warrior/ WolfriderThese are other aggressive minions that point strongly at Face Hunter.
Houndmaster extremely well.