Fluxx is a card game, played with a specially-designed 84-card deck. It is different from most other card games, in that the rules (both playing and winning) are altered throughout the game, via cards played by the players.

Rules and Gameplay
The game starts out with one basic rule, saying that each player draws one card, and plays one card during their turn. There are four types of cards in the game, which are used to alter the rules and goals of the game:

New Rule cards can be played to change the rules or add other rules. Examples are Draw 2, Play 3, Reverse Order or even Inflation (formerly X=X+1), which increases numerals on other cards played (so Draw 2 becomes Draw 3). 
Action cards, which allow the player to do one time things like steal cards or eliminate rules. Examples are Draw 2 and use 'em, Jackpot! (Draw three cards instantly), Let's Do That Again, allowing the player to search the trash pile and replay a card, and Rules Reset, which removes all new rules in play. 
Keeper cards, which are used to meet the goals below. Examples are Bread, or War. 
Goal cards, which define what is required to win. Most goals require pairs of keeper cards, for example Appliances requires the Toaster and Television keepers, and Squishy Chocolate requires Chocolate and The Sun. A few goals are different, for example Brain (no TV), All You Need Is Love, and 10 Cards In Hand. 
Blanxx are cards purchasable in packs of 15 semi-blank cards used to create custom cards to change gameplay further. Fluxx Blanxx booster packs are sold for $3, including one booster card for Chrononauts and two advertisements for Looney Labs. The most recent edition of Fluxx, version 3.1, contains 84 cards, as compared to the promotional deck, which had 81 cards.


Versions
There have been several versions of the game, including different cards. These versions include:

Fluxx 1.0 
Fluxx 2.0 
Fluxx 2.1 
Fluxx 3.0 
Fluxx 3.1 
Stoner Fluxx (Technically Fluxx 4.20) 
Flowers and Fluxx 
EcoFluxx 
Family Fluxx 
Using Blanxx it is also possible to create entirely personalized decks.

Fluxx has also been translated into German and Japanese, in both cases with new art and graphic design (but identical gameplay). The German version has the same card mix as Fluxx 3.0, plus the "Hide Keepers"-related cards from Fluxx 2.0. The Japanese version has the same card mix as Fluxx 3.1.


History
Fluxx was created by Andrew Looney and first published by Looney Labs in 1996. The game was successful and was licensed a year later to Iron Crown Enterprises (ICE) for wider distribution. ICE went bankrupt two years later and Looney Labs has resumed publication and distribution. Looney Labs produced a revised version of the original game in 2002. Amigo Spiele, a German game company, licensed a German language version of Fluxx in 2003. Similarly, Hobby Japan licensed a Japanese language version in 2005.

In 2003, Looney Labs produced a new version of the game called Stoner Fluxx, which had the same rules as the original but with a marijuana-based theme. The company donates a portion of the sales to groups advocating marijuana legalization. Surprisingly, there was no significant controversy over the game.