Wild Tic-Tac-Toe
Play an X or an O, whichever you like, every turn.
First player's turn
How to play
In Wild tic-tac-toe you don't have a mark of your own. On your turn you pick X or O, whichever you like, and put it in any empty square. Finish a line of three matching marks — a row, a column or a diagonal — and you win, no matter who put the other two there. If the board fills up with no line, it's a draw.
That changes how you think about every line on the board. Leave two of anything in a row with the third square open, and you've handed the other player the win. The quickest win only takes three moves.