Discover

Discover
Choose one of three cards to add to your hand.

Discover is an ability that allows the player to choose one of three different cards.

The three cards are randomly selected from a pool of all eligible cards, as stated by the card text. If not stated, the pool of cards consists of all eligible neutral and class cards matching the player's current hero class, with neutral and class cards weighted equally in being selected. By default, the chosen card is then generated and added to the player's hand, unless otherwise specified in the card text.

Functionality

All Discover effects feature card selections restricted to specific criteria. Some examples are listed below:

• Stonehill Defender allows the player to add a Taunt minion to their hand.
• Primordial Glyph allows the player to add a spell to their hand.
• Golden Scarab allows the player to add a 4-cost card to their hand.
• Arch-Thief Rafaam offers the player a specific selection of unique uncollectible cards to add to their hand.
• Shadow Visions allows the player to add a copy of a spell from their deck to their hand.
• Boom Squad offers the player exactly one Lackey, one Mech, and one Dragon.

Some Discover effects do not generate cards to the hand and instead have other effects as specified in the card text. Some examples are listed below:

• Free From Amber allows the player to summon a minion that costs 8 or more.
• Tortollan Primalist allows the player to cast a spell with random targets.
• Sir Finley Mrrgglton offers Hero Powers from any class to replace the player's current Hero Power.
• Cleric of Scales allows the player to draw a spell from their deck.

The Discover effect involves both elements of RNG and strategy, with players having to strategize and predict what they can get out of their Discover effect to impact the board and win the game.

Notes

• The Discover effect allows the player to choose a card from a selection of three cards. The cards offered are either neutral or from the class of the player's current hero, unless otherwise specified. If there are additional requirements for the selection of the three cards specified in the card text, those conditions are met as well.
• The Discover effect by default adds the selected card to the player's hand. However, some cards have an explicit description in the card text of what will be done with the selected card instead.
  • Typically, the Discovered card is not added to the player's hand if the card text indicates that something is done to the card itself, such as generating it to a specific zone (e.g. summoning it or shuffling it into the deck). If the card text states something about the Discovered card, but does not state the position of the card, it can be assumed that the card is also added to your hand.
    • Example: Free From Amber summons the Discovered card. This requires its zone to be the battlefield. Therefore, the card is not added to your hand.
    • Example: Defense Attorney Nathanos triggers the Discovered card's Deathrattle and gives it to Nathanos. This does not require the Discovered card to leave the hand, and therefore it is added to your hand.
    • Example: Body Wrapper shuffles the Discovered card into your deck. This requires its zone to be the deck. Therefore, the card is not added to your hand.
    • Example: Power of Creation summons two copies of the Discovered card. Nothing is done with the Discovered card itself, but rather copies of the card are summoned, which means the chosen card does not need to change zones. Therefore, the card is added to your hand.
• Discover effects will not present duplicate options: each of the three possible choices will be different.
  • If there aren't enough possible options, such as using Shadow Visions when the deck only has two of the same spell, this still applies and only one copy is shown.
• Players cannot choose not to take one of the cards offered by a Discover effect. They must choose one of the options. If the turn timer expires before one of the Discover options is picked, a random option will be chosen.
• While the activation of Discover effects can be duplicated by Brann Bronzebeard, individual Discover events cannot. If a Discover effect is duplicated, the two will be separate events, with their own selections of cards. However, there is no special rule preventing the two Discovers from featuring some of the same options simply by chance.
• The card chosen by the Discover effect is not placed in your hand until the end of the current Sequence, meaning that it is possible for your hand to become full in the meantime, discarding the card you chose. For example, if you have a 10/10 card hand, play Raven Idol and have a Wild Pyromancer and Acolyte of Pain in play, the card chosen will float in the air, Acolyte of Pain triggering off of Wild Pyromancer's damage will fill your hand, and finally the card chosen will be discarded.
• If you play a Discover Battlecry minion, the first Discover effect will not put its card in your hand until the end of the current Sequence (e.g. after death processing following the After Summon Phase resolves). Then, if you control Brann Bronzebeard, you will get a second Discover effect. Note that the played minion does not have to be alive at this time, only Brann Bronzebeard does. Also, note that normally Brann Bronzebeard has to be in your control during the Battlecry Phase.
• If a secret is discovered as a class without secrets in the format, then a random secret from the class of the card itself is discovered. Otherwise, a secret from the player's current class is discovered.
• Using Discover effects as any hero card offers cards as though you were playing as the class that card originated from.
• However, using Discover effects as the Ragnaros the Firelord hero has a different behaviour depending on the card.
  • If the card with the Discover effect is a neutral card, the game randomly picks 1 of the 10 classes and offers you cards as though you played the Discover card as that class.
  • If the card with the Discover effect is a class card, the game offers you cards as though you played the Discover card as that class.
• Cards that Discover a card from your deck, like Master's Call or Cleric of Scales, will draw the card. If the card says "Discover a copy of a card in your deck", such as Stitched Tracker, it will create an extra copy.
• Cards are only considered Discover effects when they say Discover on their card text. Discover-like effects such as Build-A-Beast, Guidance, and Zephrys the Great will not benefit from Discover synergies.
• Cards that Discover random cards cannot Discover copies of themselves.

Cards

For Wild format listings, see Discover/Wild format.

Collectible

This section lists all collectible cards that have the Discover mechanic.

Swipe left or right to see the cards.

Uncollectible

This section lists all uncollectible cards that have the Discover mechanic.

Swipe left or right to see the cards.

Sources of Discover

Discover-generating cards

This section lists all cards that generate Discover cards.

For Wild format listings, see Discover/Wild format.

Swipe left or right to see the cards.

Development

• Discover is intended to provide a balance between random generate effects like Unstable Portal and regular card draw. While the latter can make games more predictable through accelerating the player's progress through their deck, and the former can prove too unpredictable due to the extremely large and non-class limited pool of potential cards, Discover effects are intended to add variety to games without excessively disturbing class balance, and while still allowing players some control over which card they gain.
• The Discover ability was originally called "Treasure", a name which is still found in the game's strings. The original idea was pitched by Mike Donais, before design work had started on The Grand Tournament, but the developers did not start experimenting with adding it to cards until they began work on The League of Explorers.
• The developers tried different places for the Discovered card to go, including the top of the deck, and shuffling it into the deck at random. The former proved problematic because of shuffle into deck effects, which not only adds cards to the player's deck but also shuffle the entire undrawn deck; as a result, activating such an effect after a Discover effect would cause the chosen card to become lost in the player's deck, losing much of the value and making the mechanic less reliable. Conversely, if this didn't happen, the card drawn at the start of the next turn would already be known by the player. This removed the surprise at the drawing of an unknown card, and in tough situations often led to a feeling of powerlessness, since the player would know in advance that they were not going to draw next turn a card that was capable of dealing with the state of the board; or otherwise know in advance that they would draw the card they needed, thus taking "the drama and excitement" out of the game. The idea of shuffling the chosen card into the deck was likewise discarded due to the likelihood of the match ending before the card was drawn, thus making the effect feel unimportant and unreliable. In addition, adding the card to the top of the player's deck was an a further innovation on top of the Discover effect itself, and the designers felt it wiser "not try to do too many things all at once in a new mechanic".
• In terms of card balance, through playtesting the designers found that Discover was in most cases fairly similar in value to a card draw effect. This allowed them to use the established weighting of card draw effects to guide them in choosing stats for Discover minions.
• One of the last decisions made during the development of Discover was to restrict the effect to neutral and class cards. Prior to this, Discover effects were able to generate any card. With a far larger card pool to choose from, this made it much harder for players to predict which card an opponent's Discover effect had provided, and making the effect almost impossible to play around. The game-wide card pool also produced too much "class bleed", with other classes gaining access to the cards of other classes on too frequent a basis, weakening class uniqueness.
• The final tweak to the ability was to increase the likelihood of class cards appearing, eventually set to four times the normal chance. This was made in order to balance the far larger number of neutral cards, ensuring that class cards would be well-represented. A similar solution had already been put in place for Arena. Note that after Patch 15.2.0.33717, cards that Discover from a random pool no longer apply this class bonus.
• After exploring the ability with The League of Explorers, the developers began experimenting with ways to feature Discover in a Tavern Brawl, partly because they were also working on the first round of Tavern Brawls at that time.
• It was eventually decided for the Discover mechanic to debut through the Captain Blackheart's Treasure Tavern Brawl in October 2015. However, technical problems prevented this, and the keyword was instead announced in November at BlizzCon 2015 with its accompanying adventure, The League of Explorers.
• Discover was developed "kind of" independently of The League of Explorers. Ben Brode states, "We just kind of smashed them together and it turned out that they felt very natural together." The name change from "Treasure" to "Discover" was influenced by the keyword's debut with the adventure, though.

Trivia

• When the Discover mechanic was introduced, all cards with this mechanic would add the chosen card to the player's hand. This is still reflected in the tooltip that is shown when hovering the mouse over a card with this ability, even though this is no longer true in all cases.
• Before the introduction of Lifesteal in Knights of the Frozen Throne and subsequent expansions, Discover was the only non-launch keyword to continue to appear on cards outside of the set it was introduced in.
• Before Patch 15.2.0.33717, class cards had four times the weighting of neutral cards, meaning that they were presented as options four times more often than they otherwise would be. But because of the far larger pool of neutral cards than those of any given class, in many cases neutral cards were still more commonly presented than class cards.
  • For example, during the time of The League of Explorers adventure, the probabilities when playing Jeweled Scarab as a warlock were reported as a 10% chance for a class minion, 20% chance for a class spell and 70% chance for a neutral minion. This roughly matched the number of each type of card available: 3 warlock minions, 4 warlock spells, and 62 neutral minions (taking into account the 4x modifier for class cards). However, the probabilities for a mage playing Jeweled Scarab were reported as closer to 50/50 between class and neutral cards. Again, this matched the number of cards available: 16 mage cards and 62 neutral cards.

Gallery

Discovering a new Hero Power

Patch changes

• Server-side patch (2020-08-13):
  • Discover cards can no longer Discover themselves randomly.
  • Cards that 'generate a random card' can no longer generate themselves.

Dev comment: Overall, this change is aimed at helping games feel a bit more varied. While generating the same card can be an exciting individual moment, these types of experiences tend to have diminishing returns after a while. These adjustments should make for healthier games against classes with a ton of resource generation.

For more info and examples, see Game Mechanics Updates.

• Patch 15.2.0.33717 (2019-09-10): Cards that Discover from a random pool no longer apply a class bonus.

As Discover pools have gotten more specific, some are too narrow and repetitive. This change will increase the variety of cards from random Discover pools.

• Patch 4.0.0.10833 (2015-11-10): Added.