Mini-set

Mini-sets are supplemental card set additions to the game of Hearthstone. Similar to Adventures, Mini-sets introduce a small number of cards into the game, with each one including 35 cards. These cards are considered to be part of the expansion released previously, and combine themes and mechanics from various expansions throughout the year. They are used primarily to create and build decks to play in Casual or Ranked mode, in either the Standard or Wild game format modes. These cards are obtained chiefly through purchasing and opening card packs, through crafting, or through earning Arena rewards, but can also be purchased in bulk as part of a limited-time bundle.

Hearthstone's first mini-set was Darkmoon Races, released January 21st, 2021.

List
As of Patch, there are currently mini-sets in Hearthstone.

Darkmoon Races


Darkmoon Races is Hearthstone ' s first mini-set, featuring 35 new collectible cards. It was released on January 21st, 2021. Expanding upon the setting at Madness at the Darkmoon Faire as well as Ashes of Outland and Scholomance Academy, this set takes place at the breakneck trails at the fairgrounds, as racers from Outland, Scholomance, and Darkmoon all compete for glory.

Darkmoon Races is considered part of the Madness at the Darkmoon Faire expansion.

Wailing Caverns


Wailing Caverns is Hearthstone ' s second mini-set, featuring 35 new collectible cards. It will be released on June 3rd, 2021. Expanding on the story of Forged in the Barrens, this set follows Rokara and her party as they venture into the Wailing Caverns. This is no ordinary adventure however, as the Wailing Caverns have been twisted by the nightmares of Archdruid Naralex and are home to sinister Druids of the Fang.

Wailing Caverns is considered part of the Forged in the Barrens expansion.

Mini-set cards
Mini-set cards are cards added to the game through mini-sets. These small sets are available a few months after its parent expansion, and are included in card packs from the previous set.

How to get
All Standard format expansion cards are obtainable through card packs, through crafting, or as Arena rewards. Standard expansion cards may also be found in the Highest Rank Bonus chest at the end of each Ranked season.

Wild format expansion cards are obtainable through crafting or card packs.

Additionally, mini-sets can be purchased in their entirety in a limited-time bundle after their release, for the following prices:

Design
Mini-sets were introduced because the development team felt that the four months between major content patches was too long. They tried other content before, like Rise of the Mech and Doom in the Tomb, but they weren't the big shake-ups they wanted.

The challenges with mini-sets are the increased cost of the game, as well as the increased production cost for the developers. The team hopes to combat the first issue with the improved rewards system and the price scheme for the mini-sets, which has been received positively. As for the dev cost, Dean Ayala noted that "[they] have a good pipeline for it, but [it's] still challenging."

To tackle the increased number of things players need to memorize, mini-sets are designed to be fairly simple. They're very unlikely to introduce a new keyword, and if they do they'll make sure to peel back the complexity of the expansions before and after it.

Trivia

 * Galakrond's Awakening can be considered the prototype for mini-sets, since it features 35 new cards that continue the theme of Descent of Dragons, was released outside of the traditional expansion cycle, and brings back keywords and mechanics from the Year of the Dragon. However, it differs in that it still featured an adventure which had to be completed to earn cards, and the cards themselves are not officially part of Descent of Dragons.