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Trespass (1979) AKA Buffalo/Bison Board Game Review and Rules

Trespass (1979) AKA Buffalo/Bison Board Game Review and Rules

Originally released back in 1975 under the name Prärie, Trespass has undergone several changes throughout the years. The game was originally called Prärie but a couple years later was renamed and re-themed into Trespass by Lakeside. Twenty years later the game was once again renamed and re-themed by Piatnik and became Buffalo/Bison. The main reason why the game was able to change so many times is that it is an abstract strategy game so the theme doesn’t really matter. In general I have some mixed feelings about the abstract genre. The games usually rely entirely on the gameplay/strategy as there is no theme to help support the game. While I never thought Trespass was going to be a great game, I was intrigued because the gameplay seemed interesting. Trespass has some interesting ideas that could have made for a good game but it has some serious balance issues that lead to it being kind of a boring.

How to Play | My Thoughts | Should You Buy? | Comments

How to Play Trespass


  • Setup the game board and place it so each player is on one side of the board.
  • Choose which player will play as the attacking player and who will be the defending player.
  • The attacking player takes the eleven red pieces and places them on the spaces on the bottom of the game board.
  • The defending player places the yellow piece in the second row in the middle column. They will then place two blockers on both sides of the yellow piece.

Setup for Trespass

Playing the Game

In Trespass the players will alternate moving one of their pieces. The game begins with the attacking player moving first. They will move one of their red pieces up one space. The red pieces can only be moved in the column that they originally began in. Red pieces cannot move through other pieces.

Attacking Player Movement in Trespass

The attacking player has moved one of their red pieces.

The defending player will then get to move one of their pieces. The defending player has two different types of pieces.

The black pieces can be moved in any direction (horizontal, vertical, diagonal). The pieces can be moved as far as you want in the chosen direction until you run into the side of the board or another piece. A black piece can never be moved through another piece. The black pieces also can never be moved to the top or bottom row.

Defending Player Moving in Trespass

The defending player has moved their black piece diagonally to block the red piece that was moved.

The yellow piece can be moved one space in any direction. The piece cannot be moved to a space occupied by a black piece and it can’t be moved to the top or bottom row. When a yellow piece is moved to a space occupied by a red piece, the red piece is pushed out of the board. This piece is eliminated for the rest of the game.

Knocking Out A Piece in Trespass

The defending player can move their yellow piece one space diagonally either left or right to eliminate the red piece on the space it is moved to.

The attacking player then takes their next turn.

End of Game

The game can end in one of two ways.

If one of the red pieces reach the top row, the attacking player wins the game.

Attacking Player Winning in Trespass

One of the red pieces have reached the top row so the attacking player has won the game.

If all of the red pieces have been removed from the board or are blocked by the black pieces, the defending player wins the game.

Defending Player Winning in Trespass

The defending player has eliminated all but four of the red pieces. As the four red pieces have been blocked by black pieces, the defending player has won the game.

My Thoughts on Trespass

Although Buffalo and Bison utilize a Buffalo/Native American theme, at its core Trespass is the very definition of an abstract strategy game. In a lot of ways it kind of plays like a modified game of Chess. Instead of both players attacking one another, one player is an invading force while the other tries to hold them back. The attacking player is basically given eleven pawns that are unable to attack. Their goal is just to get one of their pieces to the other side of the board. As they can only move their pieces forward one space at a time, the attacking player needs to use deception along with spreading the other player’s forces thin in order to succeed.

To prevent the other player from reaching the other side of the board, the defending player has pieces that can block and remove the other player’s pieces from the board. While the defending player has quite a few less pieces (five versus eleven), their pieces are considerably more powerful. Their pieces can move in any direction instead of just moving up one row each turn. This gives the player a lot more flexibility as you have more options about how to traverse the board. This is key because they have to block the whole board with less pieces than the other player. Basically the defending player has to be wise in using their blockers in order to give their yellow piece the opportunity to remove red pieces from the board. If the defending player is able to remove seven pieces from the board, they are basically guaranteed to win the game.

Before you start playing Trespass you will likely think that the defending player has no chance of winning the game. The attacking player has a lot more pieces after all. With only five pieces you would think it would be hard to guard the entire board. When you start playing the game though you come to quickly realize that the defending player actually has a pretty big advantage. This comes from the fact that the black pieces can move as many spaces as they want in any direction. That makes it really easy to move a blocker to any location on the board and immediately block off an attacking player’s piece neutralizing it. You can then eventually move the yellow piece to the spot and eliminate the piece from the board entirely. The blocker that was blocking that piece can then be used to block another piece.

When both players don’t have experience with the game, the defending player has a huge advantage in the game. Outside of the defending player making a mistake, I don’t see the attacking player winning very often. The defending player can basically just mirror the attacking player’s moves. Since they have more flexibility when moving pieces, they are likely to stop the other player pretty easily. Initially I thought the defensive player was almost guaranteed to win the game outside of a colossal mistake. Until you find the right strategy as the attacker, you are going to have a hard time winning the game as the attacker.

From what I could figure out the best strategy for the attacking player is to try and stretch the defending player as thin as possible. The defending player can at max defend five of the eleven columns. Therefore you need to divert the defending player’s resources and then attack the areas that they can’t defend. In particular you might want to press forward as quickly as possible on the outside columns. If the other player doesn’t immediately block the outer pieces, you should keep moving them forward until the player eventually blocks them. This helps you because each step forward you are able to move a piece, the more ground you have gained. Unless the defending player eventually removes the piece, the defending player has to keep their blockers closer to the top of the game board which allows you to move the pieces at the bottom without having to worry about being blocked. If you alternate between attacking opposite sides of the board, the defending player won’t be able to defend the entire board.

As there are strategies that both sides can implement, Trespass feels like it would be a good abstract strategy game. The game has some interesting ideas that could have made for a good abstract game. The problem is that the game never feels like it is balanced. At first it seems like the defending player has a huge advantage. Then the attacking player figures out a good strategy to stretch the defending player’s forces. At this point it feels like the attacking player will always win if they follow the same strategy. I have no idea if Trespass actually has a strategy that you can always follow in order to win the game. It feels like the type of game that would have a solution though.

So you would think that you could just alter the number of pieces that the players get to balance the game. If the defending player always wins, either remove one of the defensive pieces from the game or allow the attacking player to move more often. If the attacking player keeps winning, remove one or more of the red pieces. This seems straightforward but it doesn’t work as well as you would think. Removing some of the pieces just flips the advantage to the other side. I don’t know if there is a way to truly balance the game where one side doesn’t have an advantage.

This leads to a problem where once a player comes up with a good strategy, they are probably going to just repeat it every game. If there is actually a solution to the game, why would a player who figures it out ever not use it. For this reason I can see the game getting repetitive pretty quickly. Once both players have developed a good strategy they will just use it every game. The outcome will then come down to who makes the most mistakes. After a couple games I fear every game of Trespass will basically be the same.

This is a shame because there are things I like about the game. If you could figure out some way to tweak the rules where both sides are balanced, I think Trespass could be a pretty good abstract strategy game. The game has a good framework. It is quite easy to play as the rules are really straightforward. You can teach the game to new players in a couple minutes as you only need to learn what you can do with the three types of pieces. The game also plays quite quickly. I would say most games only take five to ten minutes to play. With how short the game is, you can easily play a couple quick games where both players have an opportunity to be both the attacking and defending player.

On the component front I can only really comment on Trespass. Trespass’ components do their job but not much else. The pieces are quite sturdy and work as intended. The problem is that the components are really dull. There is also the fact that you could easily make your own version of the game. All you would need to make your own version of the game is eleven pieces of one color, four pieces of another color, and one piece of a third color. Then you could either use a board that has a 11 x 7 grid or you could make your own grid. That is literally all you need to be able to play the game. While the wood pieces for Buffalo/Bison look pretty nice, if you want a cheaper solution you can easily make your own version of the game.

Should You Buy Trespass?

I have to admit that I was a little disappointed by Trespass. When you first look at Trespass it actually looks quite interesting. The game kind of plays like a game of Chess where one player is the defender and the other is the attacker. The defender tries to block off the other player until they are able to eliminate enough pieces where they can block the remaining pieces. Meanwhile the attacking player tries to stretch the other player too thin so they can get one of their pieces to the top. This is a good premise for an abstract strategy game as each player tries to outsmart the other player. The game is also quick to learn and play. The problem with the game is that it never seems balanced as one side seems to always have a significant advantage. If you try to weaken one side, the other side then has a big advantage. Players will eventually lock into a strategy and then the game just repeats itself over and over again. This leads to the game becoming pretty repetitive.

If you have never cared for abstract strategy games, Trespass is not going to be for you as it is your typical abstract strategy game. If you really like abstract strategy games, there are things to like about Trespass. I think you will have to be willing to come up with some good house rules though to fix some of the game’s balance issues. If the game sounds interesting to you and you can get a good deal on it, it may be worth checking out Trespass/Buffalo/Bison.

If you would like to purchase Trespass you can find it online: Amazon, eBay


Monday 2nd of September 2019

I don't see how the attacker can lose this game. just simply ever advance the empty lane farthest from the yellow piece (if distance equals it doesn't matter what lane to advance) results in automatic win or does it not?


Monday 2nd of September 2019

Ah, ok, thought too much in only one pattern... needed to bee much more agressive, just won! =)