Ba shi fen (八十分) -- 80 points, also known as tuo la ji (拖拉机) -- tractor, is a more complicated version of si shi fen (四十分) -- 40 points. The game is usually played by four people, with your partner sitting across from you using two decks. Skip to just read my story about how I learned the game.

Goal:
     To win as a team. The game is similar to hearts, thus during each hand you want to win points. When all the hands have been played and the round is over, the winning team is awarded point(s). When the team has reached up to the Ace, the game is over (or it can be done at any point earlier, for quicker games).

Trump Card and Suite:
     One can randomly choose a player to start, from there, two decks of cards are used and players take cards one-by-one in the middle going clockwise. During the first round only, the first player to pick up a 2, must place it down for all players to see.
     In this game, there is a trump suite and a trump card. During the first round, the trump card will be all the 2's. The trump suite will be determined upon what first 2 comes up (clubs, spades, hearts, or diamonds). It is important to remember that the trump card is considered part of the trump suite! Each new round can produce a different trump card and suite. Thus, the trump card can change from 2 to Ace, and the trump suite can change between the four suites.
      After the first round, the trump suite is determined by whoever places the first trump card down. However, that can be changed if another player places two of the same trump cards down of another suite (remember, two decks).

Card Order:
     Once the trump suite is established, the card order goes as follows: Red Joker, Black Joker, Trump Card 2 of the Trump Suite, Trump Card 2 of the other suites, Trump Suite Ace down to Trump Suite 3. The non-trump suites go from Ace down to 3.
     The card order can change as the trump card changes. For example, the trump card can be a 7, making the order as follows: Red Joker, Black Joker, Trump Card 7 of the Trump Suite, Trump Card 7 of the other suites, Trump Suite Ace down to Trump Suite 2 (skipping the 7 between 8 and 6).

Points:
     5's are worth five points, 10's and K's are worth ten points within the hands.
     Within the round, there is a team that is on the offense and another on the defense. The team on the defense is trying to prevent the offensive team from reaching 80 points. If the defensive team prevents the offensive team from reaching 80 points, they gain a game point. Game points are given by starting at 2 and going up to Ace. If the offensive team does not get 80 points, then the defensive team goes up to the 3. If the offensive team does not get 40 points, the defensive team goes up to 4. If the offensive team does not get any points, the defensive team goes to the 4.
     Vice versa, if the offensive team gets to 80 points, then it is their turn to "serve" and try to win game points starting at 2. If the offensive team reaches 120 points, then they will go to 3. If they reach 160 points, then they go to 4.
     Game points determine what the trump card is for the next round.

Basic Rules/Play:
     Players pick up cards in a clockwise order. During the first round only, the first person to pick a 2 will place it out for everyone to see. That 2's suite becomes the trump suite unless another player plays two trump 2's of the same suite. Players continue to pick up cards until eight cards are left in the middle. The player who started takes the last eight cards, adds it to his/her cards and discards eight cards face down for no one to see.
     Once that has been down, the player who started chooses what cards to play. More than one card can be played only if the cards match by suite and number. Also, if a player has two pairs of the same card and suite consecutively (aka 4,5), then four cards can be played at once. Six cards can be played in this way also.

     As with hearts, whatever suite is played, all the other players must play the same suite. If one player cannot play in that suite, any other suite can be played. Trump suites beat out all the other suites to win each hand. If no trump suites are played, then the highest card within the starting suite wins.
     Remember: both teams are collecting points, even if on the offensive or defensive, so give points to your partner if you can do so.

     If pairs are played, players must play a pair in the same suite if they have them. If not, then they have to play two cards in that suite. If the starting suite is not a trump suite, then only a trump pair can beat the original non-trump suite pair.
     Remember: If 3's are the trump card, then the 4's and 2's are considered to be consecutive, as is Black Joker and the Trump Card or the Trump Card and the Trump Suite Ace.

     On the last hand of the round, whoever wins gets the last eight cards. Any points placed in those eight cards double only for the offensive team and is added to the final score. If the defensive team wins, the points are moot.

     Points are tallied, and then game points are given, deciding what the next trump card will be for the next round. Play continues as before, except that players no longer have to play the first trump card down, choosing to wait until they want to.

Special/Additional Rules:
    There are certain instances where you can play more than one card not consecutively, for example, an Ace and a pair of 6's. In this case, the player believes that they can win those three cards, and can only be beaten with an Ace and a higher pair in the same suite or a trump pair and any other trump card.

     As the round nears the end, players with many cards in the same suite can try their luck by placing all the cards they have in that suite, even if there are no pairs. However, if any player (including one's teammate) can beat the lowest card in that suite played, then all the cards except the lowest card are taken back and play continues. If no one can, then the only way to win the hand is to have as many trump cards as the number of non-trump cards played (eg: 4 non-trump suite cards defeated by 4 trump suite cards).

     At the beginning, if a player has two Jokers of the same suite, they may place the two Jokers down to play a special type of Ba Shi Fen. In this case, instead of the usual four types of suites (three non-trump suites and one trump suite), there are now five suites (four non-trump suites and the Trump Cards + Jokers suite).

Other Sites:
     Rules of Card Games: Tractor
     中国游戏中心

Background Story:
     Well, since the game is a mainland Chinese game, I picked it up when I was in Shanghai. My dormmate had a Chinese roommate who's girlfriend taught me a different version called Five of Hearts (五红桃) and I was interested in learning more. So, since I was at ECNU (华师大) and often went to the English Corner, I stated my interest in all types of games, including card games, and two girls (Ivy and Joanna) took time out of their busy lives to teach me this awesome game which I thank them for.
     The game itself is quite complicated and the rules are a little complex, but if you're a fan of tough games, this is one to definitely learn! Be sure to have a good partner at this game, it makes all the difference!