Hearthbreaker is an open source Hearthstone simulator for the purposes of machine learning and data mining of Blizzard's Hearthstone: Heroes of WarCraft. It implements every card in the game. Every attempts has been made to mimic Hearthstone precisely, including edge cases and bugs. The results of playing simulated games can be used to determine cards which work well together and cards which do not.
Hearthbreaker is not designed to allow player to play Hearthstone against each other, nor is it designed to play against human opponents within Hearthstone itself. It is designed to be used as a library for analysis.

• Documentation (In Progress) http://danielyule.github.io/hearthbreaker/
• Travis CI Build Status:
• Coveralls Code Coverage:
• Developer Mailing List: Google Group

Hearthbreaker is compatible with Python 3.2+ and PyPy3 2.3+

###Console Application

There is a basic console that you can use for playing against a bot. The bot you are playing against chooses its moves at random.

Start the console with python hearthbreaker/ui/text_runner.py deck1.hsdeck deck2.hsdeck. The two deck files are in cockatrice format, with a card name in English on each line, preceded by a number to specify how many. For example:

2 Goldshire Footman
2 Murloc Raider
2 Bloodfen Raptor
2 Frostwolf Grunt
2 River Crocolisk
2 Ironfur Grizzly
2 Magma Rager
2 Silverback Patriarch
2 Chillwind Yeti
2 Oasis Snapjaw
2 Sen'jin Shieldmasta
2 Booty Bay Bodyguard
2 Fen Creeper
2 Boulderfist Ogre
2 War Golem

The character class is inferred from the cards present, or defaults to mage.

The console application requires ncurses, which should be included with python on *nix and mac systems, but if you are on windows, you must download it from http://www.lfd.uci.edu/~gohlke/pythonlibs/#curses

###Unit Tests The tests are located in the tests package.

All tests can be run with the following command: python -m unittest discover -s tests -p *_tests.py

For Python 3.2 and PyPy3, the unit tests are dependent on the mock package.

All cards currently released by Blizzard are implemented. The engine is complete, and nearly ready for use in machine learning. Work is now being done to make the game copyable and serializable in any state. See the developer mailing list for more details.

Almost all of the game logic is found in hearthbreaker.game_objects. The game functions largely on an event based system. The events use a bind/trigger mechanism. For an overview of the events and the parameters they receive, see events.md.

The game is made up of players, each of which has a hand of cards, a hero, secrets and minions. Decisions are made by agents, which can either by computer controlled or human controlled. The system is callback based, in that when it is time to make a decision, the game will request the decision from the agents, rather than the agents dictating how the game is run.

The cards themselves are each a class, and can be found in the hearthbreaker/cards directory, organized by type (spell/minion/secret/weapon) and by class.

This project also includes a replay facility, which allows for games to be recorded and played back. The format for the replay syntax is documented in replay_format.md.

To contribute, simply fork the repository, make changes and submit a pull request.

All pull requests which implement new cards must also include a unit test for those cards. In the case where the card has no side effects aside from playing the minion, tests should include another card's effects on it.

All pull requests will be automatically verified through travis-ci.org, and a coverage report generated through coveralls.io

For more specifics about contributing, see the contributing page, or join the Developer Mailing List

A collection of Hearthstone AI related projects can be found at hs-ai.com

###HearthSim Hiroaki Oyaizu has created HearthSim, another Hearthstone simulator, written in Java with a stronger focus on efficiency and AI modelling. It currently has fewer cards implemented, but has a much more sophisticated AI.

###Focus Raffy is working towards a Domain Specific Language (DSL) for Hearthstone Cards, written in JSON. The cards are completely defined, but the engine (called Focus) is still in progress. These will allow for anyone to define new cards, by simply writing a JSON object to represent the card.

###Fireplace Jerome Leclanche is attempting to reverse engineer the xml format for the cards associated with Hearthstone and build an engine based on that. His work can be found on Fireplace GitHub page

###Soot Soot is a slightly out of date Clojure implementation of all cards in Hearthstone. It's not clear how well the implementations work. It is interesting for its functional implementation of the cards.

Hearthstone: Heroes of WarCraft and Blizzard are trademarks of Blizzard Entertainment.