Bohnanza is a German-style card game based on the game mechanics of trading and politics, designed by Uwe Rosenberg and released in 1997 (in Germany) by Amigo Spiele and more famously in England by Rio Grande Games.
It is played with a deck of cards with illustrations of eleven different types of beans of varying scarcity, which the players are trying to first plant and then sell in order to make money.
Each player is dealt five cards to start the game. In Bohnanza cards in hand are kept in the order they are dealt and must be played in that order as well. On BGA this means the first card in your hand is the rightmost (and bottom-most if your hand gets large enough for multiple rows). Each turn consists of two main phases.
For games with three players, each player will have three available fields in which to plant beans. For games with four or five players each player will have two available fields in which to plant beans. (Note, an alternate version of the Bohnanza rules exists which includes, among other things, the option to purchase a third bean field. This is version is not available on BGA and as such there is no means to purchase a third bean field.)
On their turn a player *must* plant the first bean in their hand, unless they have no cards in hand at all. They then may choose to plant the next bean or not. Players must always plant at least one bean to start their turn, and never plant more than two in this phase. If a player does not have room to plant a bean they may harvest one of their fields first to make room, possibly earning money for the beans in the process. (See planting and harvesting below)
After planting one or two beans, the player then draws and reveals two cards from the draw deck. All players may then offer trades using the revealed cards and the (still hidden) cards in their hands.
All trades must involve the player whose turn it is (referred to as the active player). Other players may not trade with each other at this time. Players may offer bean cards and request bean cards in any amount, including offering or requesting a bean for nothing, or requesting multiple beans for one. Most of the game revolves around making beneficial trades in order to plant your beans, or to avoid having to plant beans that you do not want to. Cards that were traded this turn will be planted this turn and cannot be traded again, even by the active player. BGA hides traded cards until it is time to plant them to help avoid confusion in this regard.
Once either the active player or all other players have chosen that they are done trading, beans that were traded and any revealed cards that were not traded must be planted. Unlike beans from a player's hand, these may be planted in any order and all of the beans must be planted at this time.
Once all beans have been planted the active player draws three cards, adding them in order to the back of their hand, and play passes to the next player.
An example of trading on BGA is offered below.
Planting and Harvesting beans
Beans can only be planted into empty fields or into fields that contain the same type of bean. If a player must plant a bean and does not have a field into which it can be legally planted they must first harvest a field. Harvesting bean fields often (but not always) earns a player money. The amount of money is determined by the type and number of beans in the field. Bean cards have stacked coins and numbers across the bottom of the card that indicates how many beans of that type are required to make a particular amount of money when harvested. There is also a number on the top of the card showing how many of that type of bean are in the deck to start.
When a field with enough beans to be worth money is harvested, one card for each coin is removed from the game and placed in the harvesting player's "gold pile". The rest of the beans are placed in the discard pile. For instance, blue beans require four beans in a field to be worth one coin, and six beans in a field to be worth two coins. When a five-bean field of blue beans is harvested, one of the blue bean cards is put in the player's gold pile and the other four blue beans are put in the discard pile.
When harvesting fields a player may choose any field to harvest with one restriction. Fields with only one bean card may not be harvested unless all your fields have only one bean card. Thus a player with a blue-bean field with one card, a stink bean field with two cards, and a garden bean field with one card *must* harvest the stink beans and gain no money for the field.
In the BGA implementation, fields are only harvested when necessary in order to plant a bean of a different type, and at the end of the game.
The game ends after the draw deck has been exhausted three times. Each of the first two times the draw deck is exhausted the discard pile is shuffled into the new draw deck. At this point players automatically harvest all their fields and the player with the highest total money wins. Ties are broken with turn order, the win going to the player furthest from the starting player.
On BGA the trade system is set up so that the active player has final say in any trade, but can only accept offers made by the other players. For example, Player A is the Active player, showing a blue bean and a red bean. They post a trade offering one blue bean in exchange for a stink bean and choose to wait for the other players. Player B has a stink bean in hand so decides they would like to make that trade. They click on the proposed trade (making it their active trade) and choose to post the trade. From their perspective they are offering one stink bean for one blue bean. Satisfied, they then also choose to wait for Player A.
Meanwhile Player C is hoping for a Soy bean, so posts their own offer of one red bean for one soy bean. They also have a chili bean they really don't want to plant first in their hand, so they post an offer of one chili bean asking for nothing in return. They then also choose to wait for Player A's choice.
When Player A gets back to the game, they see the three offers. Noting Player B's matching offer they click the posted offer and choose accept trade. The chosen cards are then exchanged, removed from the player's hands and/or the revealed cards. Player A doesn't have a soy bean, so chooses and rejects the trade offer, but does want the red bean. They also have a chili bean which they don't want so they post a new trade, one chili bean for one red bean, and wait again.
Player B is statisfied with the trades made and chooses Done Trading to no longer be notified of trades this round and no longer be able to make any trades this turn themselves.
Player C really doesn't want two chili beans, and not wanting to give up the red bean for anything less than soy, chooses to be done trading this turn as well.
With both non-active players having chosen to be done trading, trading is closed and traded beans must now be planted.