In Hearthstone, each player is represented by a hero. Each hero starts with 30 Health. If that value is reduced to zero, the hero will be destroyed thus losing the game. Each hero represents one of the 9 classes, determining which class specific cards can be put into the deck. Heroes also come with their own hero power, a special ability which further defines the play style of that class. Each hero represents a major character from the Warcraft universe and has their own portrait and emotes.
Players can choose which hero to play and create custom decks for each class. All players begin the game with Jaina Proudmoore (mage) and can unlock the other heroes by defeating them in Play mode or Practice mode.
Heroes by default do not have an Attack value, but can use various means to gain Attack or equip weapons. Heroes with an Attack value can attack other targets, similarly to minions, and will take damage from targets they attack accordingly.
Each hero begins at level 1 and can gain levels through earning sufficient experience (XP). Heroes can reach a maximum of level 60. XP is gained through winning games in any game mode. Winning games against real players awards bonus XP.
Up to level 10, reaching every other level with a hero will unlock a pair of new basic class cards. Above level 10, golden versions of existing class and neutral cards are granted upon reaching certain levels. Raising your first class to level 10 also completes the hidden "Level Up" quest, awarding the player one card pack. Experience and level do not affect gameplay in any other way, and are therefore only truly significant up to level 10.
Experience earned per match appears to be based on either the number of actions taken or the number of cards played during the course of the match. For example, winning or losing a game where the player played no cards and took no actions will reward no XP.
Currently, there are 9 different heroes to choose from. For a comparison and overview of the classes, and the strengths and abilities of each hero, see class.
- Malfurion Stormrage (Druid)
- Rexxar (Hunter)
- Jaina Proudmoore (Mage)
- Uther the Lightbringer (Paladin)
- Anduin Wrynn (Priest)
- Valeera Sanguinar (Rogue)
- Thrall (Shaman)
- Gul'dan (Warlock)
- Garrosh Hellscream (Warrior)
Playing the warlock card Lord Jaraxxus destroys the warlock and replaces him with the Lord Jaraxxus hero. This new hero is still under the control of the player, but has its own portrait, emotes, and hero power. However, Jaraxxus cannot be selected as a regular hero, and any experience gained from playing as Jaraxxus will be given to the warlock class regardless of the hero originally selected before the game.
- Main article: Boss
Each boss features a unique hero power and selection of cards. Bosses may use regular collectible cards, but also have access to unique boss cards, special and often extremely powerful cards which are not available to players. Boss battles are generally designed to offer a specific challenge, usually featuring a strong theme or style, forcing the player to find a way to defeat them. Players often must alter their decks or construct new ones in order to beat specific bosses, with each having its own strengths and weaknesses.
 Golden heroes
Whenever a player completes 500 wins in Ranked Play mode with a given hero, that hero will be permanently replaced with a golden version. These are similar to golden cards, with golden borders and special animations, and will automatically be used instead of the regular version in Casual and Ranked play, as well as Duels. However, they will not be used for Arena.
Hero powers and those minions and weapons created by hero powers will also be affected, with fully animated golden versions. Specifically Searing Totem, Wrath of Air Totem, Healing Totem, Stoneclaw Totem, Wicked Knife, and Silver Hand Recruit summoned by golden hero powers will be golden.
Players can track their wins progress with each hero on the Ranked deck selection screen, with the number of wins out of 500 listed beneath the currently selected hero's portrait. Wins from before the introduction of the golden heroes feature do not count toward golden heroes.
While much of the game involves trading minions and making wise use of cards to gain control of the board, almost all Hearthstone battles are ultimately resolved through dealing damage to the enemy hero. Despite this, because of the opportunity for repeated damage presented by control of minions, it is generally more important to address the ongoing threat of enemy minions than to simply deal damage to the enemy hero. However, once the enemy hero's Health has reached a certain level, it becomes most important to simply direct all attacks at the enemy hero, regardless of the state of the board. The assessment of target priority is an ongoing strategic challenge of Hearthstone.
When the player is capable of dealing fatal damage to an enemy hero that turn (known as "having lethal"), it is always best to do so that turn. At these times, taking normally prudent actions such as removing threatening minions, rather than simply attacking the enemy hero, can in fact directly cause the player to lose the game.
Aggro decks tend to focus on dealing damage to the enemy hero as quickly as possible and sacrifice late game potential in order to provide greater power and capabilities during the earlier game. Focused on defeating the enemy before they have the chance to retaliate, these decks often ignore board control in favour of directing all attacks at the enemy hero itself.
When dealing damage, the hero is often referred to as "the face", such as in "dealing 10 damage to the face", in contrast to attacking other targets. "Going for the face" is used to describe directing attacks straight at the enemy hero.
 In development
 Alternate heroes
 Patch changes
- Patch 18.104.22.16844
- Golden Heroes have been added and now can be unlocked after winning 500 Ranked games with a Hero! Track your progress on the deck selection screen in Ranked Mode.
- Unlocking a hero now plays that Hero’s emote. Well met!
- Patch 22.214.171.12490 - The maximum level is now 60, and you can earn XP in any game mode up to max level.
- Reddit (October 2013). How is experience gain caluclated in hearthstone matches?.
- Hearthpwn: Fireside Chat - BlizzCon Panel
- HearthPwn.com - Golden Heroes Coming Soon! (2014-03-06)
- HearthPwn.com - Golden heroes coming soon (2014-03-06)]
- Facebook - Hearthstone
- Buffed.de: Hearthstone: Alternative Helden-Figuren, Legendaries und Abenteuer - Entwickler im Gespräch (Google Translate)
- Dev Interview: New Heroes, Gameboards, Adventure Mode; Legends of Hearthstone BS2W2