Standard is a game mode in the Play mode of Hearthstone. It limits the legal card pool to the Basic and Classic sets and to the card released in the last two years. Currently the card sets legal in the Standard mode are Basic, Classic, Blackrock Mountain, The Grand Tournament, League of Explorers and Whispers of the Old Gods. The Standard format is used in the HCT events 
Cards that are not legal in the are still playable in the Wild format, which will always include all the cards available.
The Standard rotates each year with the first expansion.
Year of the Kraken
The first season of Standard is called Year of the Kraken, according to the Zodiac constellation on the sky of Azeroth.
The card sets legal in the Standard format are:
- Blackrock Mountain
- The Grand Tournament
- League of Explorers
- Whispers of the Old Gods
In the Wild format additional legal sets are:
- "A New Way to Play". us.battle.net. 2016-02-02. Retrieved 2016-05-21.