Abalone (board game)

Abalone is a two-player abstract strategy board game designed by Michel Lalet and Laurent Lévi in 1987. Players are represented by opposing black and white marbles on a hexagonal board with the objective of pushing six of the opponent's marbles off the edge of the board.

Abalone was published in 1990 and has sold more than 4.5 million units. The year it was published it received one of the first Mensa Select awards. As of 2011, it is sold in more than thirty countries.

Gameplay

Rules

The board consists of 61 circular spaces arranged in a hexagon, five on a side. Each player has 14 marbles that rest in the spaces and are initially arranged as shown below, on the left image. The players take turns with the black marbles moving first. For each move, a player moves a straight line of one, two or three marbles of one color by one space in one of six directions. The move can be either broadside / arrow-like (parallel to the line of marbles) or in-line / in a line (serial in respect to the line of marbles), as illustrated below.

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A player can push their opponent's marbles (a "sumito") that are in a line to their own with an in-line move only. They can only push if the pushing line has more marbles than the pushed line (three can push one or two; two can push one). Marbles must be pushed to an empty space (i.e. not blocked by a marble) or off the board. The winner is the first player to push six of the opponent's marbles off the edge of the board.

Move notation

The notation for recording moves assigns the letters a-i (or A-I) to the horizontal lines, and the numbers 1-9 to southeast-northwest diagonals.

i O O O O O

h O O O O O O

g · · O O O · ·

f · · · · · · · ·

e · · · · · · · · ·

d · · · · · · · · 9

c · · @ @ @ · · 8

b @ @ @ @ @ @ 7

a @ @ @ @ @ 6

1 2 3 4 5

There are several popular notations for the moves.

Aba-Pro notation
In-line move: fromFirst toFirst, e.g. e5f6, in the picture below, denotes moving the marbles at {e5, f6, g7} to {f6, g7, h8} (while pushing {h8} to {i9} and ejecting i9), c3b2 is {c3, b2} to {b2, a1}, ejecting {a1}.
Broadside move: fromFirst fromLast toFirst, e.g. e5g7f5 (or g7e5h7: each broadside move has two distinct notations; the unicity can be forced by adding the constraint used in Nacre, thereby only allowing e5g7f5) denotes moving the marbles at {e5, f6, g7} to {f5, g6, h7}.
Nacre notation
All moves: fromFirst toLast, only considering the friendly marbles displaced, such that the distance between the two coordinates equal the number of friendly marbles moved minus one; e.g. e5f6 in Aba-Pro becomes e5h8, e5g7f5 becomes e5h7, c3b2 becomes c3a1. The distance used is defined by the following norm: <math>\|(x, y)\| = \frac{|x| + |y| + |x - y|}{2}</math>. The constraint on the distance ensures there is a unique notation for each move. Notice the notation for a two-marble broadside move can always represent two different moves, but both are never legal at the same time; e.g. d1e3 can mean {d1, d2} to {e2, e3}, or {d1, e2} to {d2, e3}.
Extended Nacre notation, the players being possibly gathered into teams.

A number of two-player variations use a third colour for passive pieces: for example, the variation called The Pillar (with a fixed marble in the centre of the board), which has been examined in some depth by Alex Borello and Nicolas Le Gal. Another possible variation involves either player winning the game by ejecting the central marble.

A few variations use a second layer of marbles.

Grand Abalone is a variation featuring a larger board (6 cells per side), wherein the players are granted two moves per turn (except for the very first turn of the game, to mitigate the advantage of playing first). The players may move 4 of their marbles instead of 3, and must achieve a score of 10 ejections to win, instead of 6.

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Strategy

Forums of Abalone communities have found that, generally:

Keep the marbles close to the centre of the board and force the opponent to move to the edges.
Keep the marbles close together for increased defense and attack, especially in a hexagon shape to be able to push or defend in any direction.
Pushing the opponent off the board is not usually a good idea if it leads to weaknesses in the player's geometry.
Setting a "trap" by making a marble weak in one direction allows for opponent to weaken center defenses.

Champions

Person-to-person competitions have been held by the Mind Sports Olympiad since 1997.

1997: Marc Tastet
1998: Vojtěch Hrabal
1999: Gert Schnider
2000: Gert Schnider
2001: Thomas Fenner
2002: Jan Šťastna
2003: Stephane Nicolet
2004: Alex Borello
2005: David M. Pearce
2006: Jan Šťastna
2007: Vincent Frochot
2008: Jan Šťastna
2009: David M. Pearce
2010: Vincent Frochot
2011: Vincent Frochot
2012: David M. Pearce
2013: David M. Pearce
2014: Nicolas Fiorini
2015: Vincent Frochot
2016: Vincent Frochot
2017: Vincent Frochot
2018: Vincent Frochot
2019: Vincent Frochot
2020: Alex Borello
2021: Alex Borello
2022: Vincent Frochot
2023: Vincent Frochot
2024: Kang Kyungmin
2025: David M. Pearce

Gert Schnider and Thomas Fenner participated in the evaluation and adjustment of Aba-Pro. Marc Tastet was the 1992 World Othello Champion, Stephane Nicolet is a two-time World Othello Championship finalist, and Jan Stastna is a strong Othello player.

In a computer-to-computer competition held in 2003 at the International Computer Games Association (ICGA) events in Graz, Austria, the Aba-Pro program defeated the Nacre program.

In 1999, a number of top players from the Mind Sports Olympiad signed an agreement to use a different starting position (the Belgian daisy) to revitalize the game. This has been used for top tournaments since then, including the AbaCup.

Reception

In the February–March 1990 edition of Games International (Issue 13), Mike Siggins called the components "of good quality", and the rules "extremely concise." He found the game very replayable, and commented that "it has the potential to become a classic." His only complaint was that "as players become more proficient the game can slow up and stalemates often result." Despite this, Siggins gave the game an above-average rating of 8 out of 10, saying, "Abalone is one of the best abstract games to appear in a long while."

Play online

Several digital adaptions of Abalone are available:

Board Game Arena - browser-based multiplayer version.
PlayAbalone - free browser-based version with AI opponents.
PlayStrategy - free browser-based version, with real-time and turn-based play; features standard Abalone and Grand Abalone.
Steam - digital edition with local and online play.

Reviews

Games #98
' #54