Vanilla JavaScript game
View demo here at codepen.
My game has 3 levels difficulty plus for two players.
Tic-tac-toe is a paper-and-pencil game for two players, X and O, who take turns marking the spaces in a 3×3 grid. The player who succeeds in placing three of their marks in a horizontal, vertical, or diagonal row wins the game. Players soon discover that best play from both parties leads to a draw. Hence, Tic-tac-toe is most often played by young children.