Copyright (c) 1979 Knots

This game is played on a 4x4 square board. There are 12 stones off board, 3 of each color from a total of 4 colors. Each player gets two colors (i.e., 6 stones)

MOVE - On each turn, each player drops a stone on an empty cell not adjacent to another stone of the same color.
If the player cannot move, it passes.
GOAL - Wins the player that makes a 4 in-a-row of 4 different colors.
If both players are unable to achieve the goal, the game is a tie.
An example

First player has black and blue stones, while Second has white and red. It's Second' turn: if he drops a white stone at b4, First must reply with a blue stone at d4 (or Second will win with a white stone there). Then Second wins by dropping a red stone at d3.

The original rules also described a variant where it's removed the adjacency restriction and each player starts with 4 stones of each color (perhaps this variant is better). Thanks to John Lawson for providing Matrix' rules information.