Tic-tac-toe variants
Tic-tac-toe is an instance of an m,n,k-game, where two players alternate taking turns on an m×n board until one of them gets k in a row.
[2] The game can be generalised even further from the above variants by playing on an arbitrary hypergraph where rows are hyperedges and cells are vertices.
[4] It was called Terni Lapilli and instead of having any number of pieces, each player only had three; thus, they had to move them around to empty spaces to keep playing.
[6][7] Another closely related ancient game is three men's morris, which is also played on a simple grid and requires three pieces in a row to finish.
Another variant, Qubic, is played on a 4×4×4 board; it was solved by Oren Patashnik in 1980 (the first player can force a win).
For example in the case of Gobblet-like variant, Gobblet Gobblers[11] and Otrio,[12] the third element appears as variation in marker sizes (small, medium, large).
More generally, the first player can draw or win on any board (of any dimension) whose side length is odd, by playing first in the central cell and then mirroring the opponent's moves.
This means unlike in misere tic tac toe, in Notakto, both players play as the same symbol, X.
[20][21][22][23] Unrestricted n-in-a-row is played on an infinite tic-tac-toe board where the goal is for one player to get n in a row.
[2] The game called Amőba (amoeba) in Hungary is played on squared paper; it is a five-in-a-row variant.
The winner of a match gets to fence in the completed game with a tight continuous line resulting in an amoeba-looking shape, hence the name.
[29] s a b l t Another isomorphic game uses a list of nine carefully chosen words, for instance "eat", "bee", "less", "air", "bits", "lip", "soda", "book", and "lot".
[30] Tic tac toe can be played by integrating element of dexterity to place the markers.
[citation needed] In the game SOS, the players on each turn choose to play a "S" or an "O" in an empty square.
[43] If a player makes the sequence SOS vertically, horizontally or diagonally they get a point and also take another turn.
