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.
The Onyx board is a grid of interlocking squares and triangles, with pieces played on the points of intersection (as in Go). Each side of the board comprises twelve points. Black tries to connect the two vertical (black) sides with an unbroken chain of black pieces, while White tries to connect the two horizontal (white) sides with an unbroken chain of white pieces. The first to do so wins the game.
Onyx was featured in several issues of Abstract Games magazine edited by Kerry Handscomb.