Tic-tac-toe is a boring game because the optimal strategy is easy to learn. There's even a book you can play against. But here's a way to play tic-tac-toe with a more complicated optimal strategy. It's called Gobblet Gobblers. (If you have a 3D printer you can make it from these models).
How to play (From Game Rules):
The first player is determined randomly. The starting player may place any piece of any size from their characters to any spot on the board.
From here players will take turns placing their characters onto the board. Bigger characters can always "gobble" smaller characters meaning you can place larger characters over yours or your opponent's smaller ones. This takes over the spot for you.
Player's may also move their pieces around the board if they wish, but if you move and piece and uncover your opponent's piece, they now control that spot.
Also, once a piece is touched by a player it must be moved. Characters played to the board can never be removed.
