Pencil and paper games: Improving Tic Tac Toe

Among the most well-known pencil and paper abstract games are Tic-Tac-Toe, Gomoku, and Dots'n'Boxes. Another famous game that can be played with a pen is Connect4 (but many families have bought this game anyway). 

Many connection games can be also played with pencil and paper, like Hex, TwixT or Bridgit. Of course, there are other famous games in this genre like Hangman or Battleship but, as usual, we'll stick here with the abstract ones.

In this post let's check some examples that improve the playability of Tic Tac Toe, one of the simplest abstract games.

An interesting version is Ultimate Tic Tac Toe and is played on a 9x9 grid of nine 3x3 areas (like in a Sudoku board). Each player makes a move on one of the nine mini-boards. But the next player must play at the board relative to the previous opponent's move. For eg, when a player plays at the upper-left corner, the next player must play at the upper-left 3x3 board. When a player makes a 3 in-a-row that mini-board belongs to her. If a move goes to again to that finished 3x3 board, the player can choose whatever open board she prefers. Wins the player that makes a 3 in-a-row of mini-boards (play online here). A similar game is 1976's Tri-o Tri-x.

The next variant is SOS. In this game, played on a square grid of size 3x3 or larger, players can write an S or a O on an empty square. Every time a player makes a orthogonal or diagonal row with the S-O-S sequence, he crosses it with his color and scores one point. The player with highest score wins.

Another variant is 3D Tic Tac Toe, played on a stack of four 4x4 boards (a 3x3x3 version is a trivial win for the first player). So, a player wins by making a 4 in-a-row using orthogonal or diagonal lines in all three dimensions. This can be represented in a page by drawing a line of four 4x4 boards, where the leftmost board is the bottom, and the rightmost is the top. This game was published in 1947 as Qubic:

One variant designed by Trevor Truran in 1981 for Games and Puzzles #81 is Knights and Crosses:

Here's another pen and pencil game called Order and Chaos by Stephen Sniderman that appeared on GAMES #25:

[addendum] Another 3D Tic-Tac-Toe is 1969's Stop Dot, published by Mattel.

Here the game is played on five faces of a 3x3x2 cube, and the goal is to make a 5 in-a-row with five different colors (at least over two faces):

These are the rules: