Question: Which board game features a rule for performing captures, making it unique among connection games, Stratego or Onyx?

full_context: Document 1: Abstract strategy game: An abstract strategy game is a strategy game that does not rely on a "theme". Traditional abstract strategy games will conform to the strictest definition of: a gameboard, card, or tile game in which there is no hidden information, no non-deterministic elements (such as shuffled cards or dice rolls), and (usually) two players or teams taking a finite number of alternating turns.
Document 2: Blue and Gray (board game): Blue and Gray is an strategy board game for two players invented by Henry Busch and Arthur Jaeger in 1903. They obtained a patent for the game, but may never have published it. Blue and Gray was featured in the book "A Gamut of Games" (1969) by Sid Sackson. It was also featured in "The Book of Classic Board Games" (1991) by Klutz Press under the name Cats and Dogs. In this book, the game was ranked among the top 15 board games of all time, including checkers, backgammon, Go, and mancala. The game is also known as Wild West, Thumps Game, and Captain and Soldiers. The name Blue and Gray "refers to the uniforms of the South and the North in the Civil War and in the original game the playing pieces of the contestants were of those colors."
Document 3: Connection game: A connection game is a type of abstract strategy game in which players attempt to complete a specific type of connection with their pieces. This could involve forming a path between two or more goals, completing a closed loop, or connecting all of one's pieces so they are adjacent to each other. Connection games typically have simple rules, but complex strategies. They have minimal components and may be played as board games, computer games, or even paper and pencil games.
Document 4: Stratego: Legends: Stratego: Legends is a strategy board game created and released by Avalon Hill in 1999, with rules similar to "Stratego". Set in a mythical world called "The Shattered Lands", it pits the forces of good (represented by beige-back pieces) against the forces of evil (represented by gray-back pieces). It plays similar to the original "Stratego" game, and also somewhat similar to chess. The game was discontinued by Avalon Hill in 2004.
Document 5: Shogi: Shogi (将棋 , shōgi ) ( , ] or ] ), also known as Japanese chess or the Generals' Game, is a two-player strategy board game in the same family as Western (international) chess, chaturanga, makruk, shatranj, janggi and xiangqi, and is the most popular of a family of chess variants native to Japan. "Shōgi" means general's ("shō" 将 ) board game ("gi" 棋 ).
Document 6: Havannah: Havannah is a two-player abstract strategy board game invented by Christian Freeling. It belongs to the family of games commonly called connection games; its relatives include Hex and TwixT. Havannah has "a sophisticated and varied strategy" and is best played on a base-10 hexagonal board, ten hex cells to a side.
Document 7: Stratego: Stratego is a strategy board game for two players on a board of 10×10 squares. Each player controls 40 pieces representing individual officer ranks in an army. The pieces have Napoleonic insignia. The objective of the game is to find and capture the opponent's "Flag", or to capture so many enemy pieces that the opponent cannot make any further moves. "Stratego" has simple enough rules for young children to play, but a depth of strategy that is also appealing to adults. The game is a slightly modified copy of an early 20th century French game named "L'Attaque". It has been in production in Europe since World War II and the United States since 1961. There are now 2- and 4-handed versions, versions with 10, 30 or 40 pieces per player, and boards with smaller sizes (number of spaces). There are also variant pieces and different rulesets.
Document 8: Ploy (board game): Ploy is an abstract strategy board game for two or four players, played on a 9x9 board with a set of 15 pieces (2-handed) or 9 pieces (4-handed and partnership games) per player. Pieces have various horizontal, vertical or diagonal moves somewhat like chess pieces, except directions of movement are limited; pieces change directions of movement by "rotating". Object of the game is to capture the opponent's "Commander" (analogous to the king in chess), or all of his other pieces.
Document 9: Hex (board game): Hex is a strategy board game for two players played on a hexagonal grid, theoretically of any size and several possible shapes, but traditionally as an 11×11 rhombus. Players alternate placing markers or stones (Go stones make ideal playing pieces) on unoccupied spaces in an attempt to link their opposite sides of the board in an unbroken chain. One player must win; there are no draws. The game has deep strategy, sharp tactics and a profound mathematical underpinning related to the Brouwer fixed-point theorem. It was invented in the 1940s independently by two mathematicians, Piet Hein and John Nash. The game was first marketed as a board game in Denmark under the name Con-tac-tix, and Parker Brothers marketed a version of it in 1952 called Hex; they are no longer in production. Hex can also be played with paper and pencil on hexagonally ruled graph paper.
Document 10: Diplomacy (game): Diplomacy is a strategic board game created by Allan B. Calhamer in 1954 and released commercially in 1959. Its main distinctions from most board wargames are its negotiation phases (players spend much of their time forming and betraying alliances with other players and forming beneficial strategies) and the absence of dice and other game elements that produce random effects. Set in Europe before the beginning of World War I, "Diplomacy" is played by two to seven players, each controlling the armed forces of a major European power (or, with fewer players, multiple powers). Each player aims to move his or her few starting units and defeat those of others to win possession of a majority of strategic cities and provinces marked as "supply centers" on the map; these supply centers allow players who control them to produce more units.
Document 11: Shannon switching game: The Shannon switching game is an abstract strategy game for two players, invented by American mathematician and electrical engineer Claude Shannon, the "father of information theory" some time before 1951. Two players take turns coloring the edges of an arbitrary graph. One player has the goal of connecting two distinguished vertices by a path of edges of their color. The other player aims to prevent this by using their color instead (or, equivalently, by erasing edges). The game is commonly played on a rectangular grid; this special case of the game was independently invented by American mathematician David Gale in the late 1950s and is known as Gale or Bridg-It.
Document 12: Onyx (game): Onyx is a two-player abstract strategy board game invented by Larry Back in 1995. The game features a rule for performing captures, making Onyx unique among connection games.
Document 13: Sixteen Soldiers: Sixteen Soldiers is a two-player abstract strategy board game from Sri Lanka. It also comes from India under the name Cows and Leopards. A variant of this game is also popular in Bangladesh, where it is known as Sholo guti (Sixteen pieces). The game is similar to draughts and Alquerque as players hop over one another's pieces to capture them. However, unlike draughts and standard Alquerque, the game is played on an expanded Alquerque board consisting of four triangular boards attached to the four sides of an Alquerque board. Also, pieces can move and capture in any direction from the beginning. There is no promotion to King. Its actual closest relatives are Peralikatuma and Kotu Ellima which are also from the Indian subcontinent. The only real difference between these three closely related games is the number of pieces. In Sixteen Soldiers, each player has 16 pieces hence the name of the game. In Peralikatuma, each player has 23 pieces. In Kotu Ellima, each player has 24 pieces. Sixteen Soldiers is also related to the Indonesian game of Permainan-Tabal.
Document 14: Sua Ghin Gnua: Sua Ghin Gnua is a two-player abstract strategy board game from Thailand, formerly known as Siam. Another name for the game is Tigers and Oxen. It is a hunt game played on a 5x5 square grid with only orthogonal lines. One player plays the three tigers, and the other player plays the twelve oxen. The board is empty in the beginning. Players first drop their pieces onto the board, and then are able to move them. The tigers can capture the oxen by the short leap as in draughts and Alquerque, but the oxen attempt to elude and at the same time hem in the tiger. Sua Ghin Gnua most resembles the tiger hunt games (or tiger games) such as Bagh-Chal, Rimau-rimau, Main Tapal Empat, Catch the Hare, and Adugo since they all use a 5 x 5 square grid. But tiger games technically consist of a standard Alquerque board which is a 5 x 5 square grid with several diagonal lines criss-crossing through it which are completely missing in Sua Ghin Gnua. There are however some variants of Catch the Hare which have missing diagonal lines also. Another game that resembles Sua Ghin Gnua is from Myanmar called Tiger and Buffaloes which is a hunt game consisting of a 4 x 4 square grid with no diagonal lines. Myanmar happens to border Thailand geographically so there might be a historical connection between the two games. Another game from Myanmar is Lay Gwet Kyah that is presumed to be similar to Sua Ghin Gnua. Sua Ghin Gnua was briefly described by Stewart Culin, in his book "Chess and Playing Cards: Catalogue of Games and Implements for Divination Exhibited by the United States National Museum in Connection with the Department of Archaeology and Paleontology of the University of Pennsylvania at the Cotton States and International Exposition, Atlanta, Georgia 1895" (1898). It's also briefly mentioned by H.J.R. Murray in his book "A History of Chess" (1913). It was also described by R.C. Bell, in his book "Board and Table Games from Many Civilizations" (1969).
Document 15: Wythoff's game: Wythoff's game is a two-player mathematical game of strategy, played with two piles of counters. Players take turns removing counters from one or both piles; when removing stones from both piles, the numbers of counters removed from each pile must be equal. The game ends when one person removes the last counter or counters, thus winning.
ground_truth: Onyx