YMMV / Tic-Tac-Toe

• Game-Breaker: The go-to example of how mathematically solving a game works. Since there's a very limited number of game states, it's easy to memorize the optimal move for any situation, always drawing against someone who's done the same, and always winning against everyone else.
• Popular Game Variant:
  • Once the 3×3 grid gets too easy, players may trade up to a larger grid size.
  • In a "3D" variant, played simultaneously on three separate grids (to simulate a cube), where getting three in a row in any direction (even across different grids) counts as a win.
    • A manufactured version called Qubic provided both of the above in physical form: four transparent plastic boards with 4×4 grids, with metal posts to stack the layers and colored disks to represent players' moves.
  • "Ultimate Tic-Tac-Toe" adds a layer. It uses a big 3×3 grid where each cell contains a standard 3×3 board. Winning one of the small games captures the cell for the big game. As an additional twist, the cell a player marks dictates which board their opponent can play next. If X marks the center of a small board, O must make their next play somewhere on the center board of the big game.
  • X typically goes first, but that's up to preference really.

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