Any single cell may contain only one mark. Quox Played on a 3 by 3 grid, with one player putting in O 's and the other player putting in X 's in turns. In any one turn, players may put their mark in as many cells as they like, provided that all the cells used are in the same straight line vertically or horizontally but not diagonally. The cells do not have to be 'next to' each other. Wildox Played on a 4 by 4 grid.
Players take turns putting either a O or a X in any cell.
Tactox Played on a 4 by 4 grid. In any one turn, players may put their mark in as many cells as they like, provided that all the cells are in the same straight line vertically or horizontally but not diagonally and the cells used form a continuous line. The player who makes the last mark loses the game. Blox Played on a 4 by 4 grid. Cells which touch each other along a common edge may NOT have the SAME mark in them.