Every move is two decisions
In ordinary tic-tac-toe you only choose a square. Here you also choose your opponent's next board, because the square you take is a map of the big board: take the center square of any small board and they must play next in the center board; take a corner square and they go to that corner board.
So before every move, ask two questions. Is this a good square in this board? And is that a good board to send them to? The second question often matters more. A strong square that sends them where they can win a board, or block your line on the big board, is a bad move.
Finished boards and free moves on Suvi
Rule sets differ here, so this is exactly what Suvi does:
- A won board is closed. Once someone has three in a row in a small board, nobody can play there again, even if it still has empty squares.
- A full board with no line is closed too, and counts for nobody.
- Sent to a closed board, you get a free move: any empty square in any open board.
- The very first move can go anywhere.
- If every board closes with no three in a row on the big board, it is a draw. Suvi doesn't count who won more small boards.
A free move is the biggest gift in the game, and this creates dead squares. Once the top-left board is closed, say, the top-left square of every other board sends your opponent to a closed board and gives them a free move. Each board that closes adds one more square to avoid in every board still open.
Read the board you're sending them to
Look at the target board from your opponent's side before you send them there:
- Can they win it now? If they have two in a row with the third square empty, they can. Only allow that if the board is no use to them on the big board.
- Where can each reply send you? Every empty square in that board is a board you might be sent to next. If most of them send you somewhere good, it is a good send.
- How many safe squares do they really have? Dead squares in the target board are squares they can only play by handing you a free move, so their real choice is smaller than it looks.
Sacrifice moves
Sometimes the right move gives something away on purpose:
- Give away a board that doesn't matter. A small board that can't be part of any big-board line your opponent can still make is worth nothing to them. Letting them win it is fine if that send is the best one for you.
- Give up a square to gain a send. Letting them make two in a row in some board can be right if every reply they have there sends you where you want to go.
- Close a board to take squares away. When a board closes, its matching square becomes dead everywhere. If your opponent needs the bottom square in several boards to finish small lines, closing the bottom board, by winning or filling it, means they can only take those squares by giving you a free move.
Never hand over a free move lightly, though. It is often worth more than a whole small board.
Steering your opponent
- Use nearly full boards. Send them to a board with only one or two empty squares and you know almost exactly where they will send you back.
- Keep them out of the boards they need. If one small board would give your opponent three on the big board, don't play its matching square anywhere if you can help it, even when it looks like your best move.
- Make two needs at once. If you could win the game through either of two boards, your opponent has to keep you out of both, which means avoiding two matching squares in every board. Add the dead squares, and they soon run out of safe moves. It is a double threat on the big board.
Playing Suvi's computer
- Easy plays loosely and grabs a small board when it sees one. It is the place to practice reading your sends.
- Medium plans a few moves ahead, so it usually makes you pay for an obvious gift.
- Hard plays out a huge number of possible games before each move. It punishes free moves and careless sends, so beat it by making fewer of them: check the target board every time.
Against the computer you are always X, whoever starts. Undo takes back your move and its reply; a hint shows the square Hard would play.
If you only remember three things
- Your square is their board: check where you are sending them before every move.
- Closed boards make dead squares; avoid giving free moves.
- Give away boards that don't matter to win the ones that do.
Try it: play Ultimate Tic-Tac-Toe against Medium and name the board you are sending it to before every move. Looking for more? See two-player games.
Questions
- Can I play in a small board that's already won?
- Not on Suvi. A won board closes, even if it still has empty squares. If you are sent to it, you get a free move in any board that is still open instead.
- Does winning more small boards decide a drawn game?
- No. On Suvi only three small boards in a row wins. If every board closes without one, the game is a draw, however many boards each player won.
- What is a dead square?
- A square whose matching board is already closed. Playing it sends your opponent to a closed board, which gives them a free move anywhere, so treat dead squares as off-limits unless that free move can't hurt you.
- Where should I play my first move?
- Anywhere is allowed. The center board is the most valuable, but remember that whichever square you pick sends your opponent to the matching board, so the center square sends them straight into the center.
- Am I X or O?
- Against the computer you are always X, even when the computer goes first. In a two-player game Player 1 is X and Player 2 is O, whoever starts.
Play it now
Ultimate Tic-Tac-Toe is free on Suvi, on your phone or computer, no download. Also: Ultimate Tic-Tac-Toe vs Computer · 2 Player Ultimate Tic-Tac-Toe · Ultimate Tic-Tac-Toe With a Friend Online.