<p>As you know, tic tac toe is a solved game that end in a tie with optimal play.  And it's too short to really get any initiative as the second player, even for children.  Going second there is no way to <em>force</em> a win without 2 misplays from the first player.  So if you want a "strategy" for player 2, it really comes down to just not losing.  </p>

<p>As for going first, I often liked taking a corner first because it offers more opportunities for my opponent to mess up (any square but the middle is a win for the first player with perfect play).  </p>

CC BY-SA 3.0
2017-03-22T09:05:59.977Z
XKCD have a nice [graphical representation of perfect play](https://xkcd.com/832/) for both first and second player - you can add the link/image to the answer
G0BLiN
CC BY-SA 3.0
2014-12-23T03:19:12.870Z
2014-12-23T03:19:12.870Z
ryanyuyu
<p>If you are second, you will tie or lose automatically, unless your opponent is severely distracted or lets you win. In the following examples of moves and your responses, X moves first and each column is a set of two turns.</p>

<p>Example 1.</p>

<pre><code>x o - | x o - | x o -
- - - | - o - | - o -
- - - | - - x | o x x
</code></pre>

<p>Example 2.</p>

<pre><code>x - o | x - o | x - o
- - - | - x - | o x x
- - - | - - o | - - o
</code></pre>

<p>Example 3.</p>

<pre><code>x - - | x - - | x x o
- o - | - o - | - o -
- - - | - o x | - o x
</code></pre>

<p>Example 4.</p>

<pre><code>- x - | - x o | - x o
- o - | - o - | - o -
- - - | - - x | x o x
</code></pre>

<p>Example 5.</p>

<pre><code>- x o | - x o | - x o
- - - | - x - | x x o
- - - | - o - | - o -
</code></pre>

<p>Example 6.</p>

<pre><code>- x - | x x o | x x o
- - - | - - - | - o -
- o - | - o - | x o -
</code></pre>

<p>Example 7.</p>

<pre><code>- - o | x - o | x - o
- x - | - x - | o x x
- - - | - - o | - - o
</code></pre>

CC BY-SA 3.0
2017-03-22T10:47:38.287Z
I tried to salvage the post as good as it gets, however I still have to downvote it because I'm not sure what they're trying to say (whether it's supposed to be best practice, examples of turns that won't lose you the game, or simply examples of turns you could take). At least it should be somewhat readable now...
TheThirdMan
CC BY-SA 3.0
2017-03-22T12:02:55.817Z
The answer seems much more legible like this -- I'm going to do a bit more editing.
doppelgreener
CC BY-SA 4.0
2018-07-20T13:31:52.553Z
In your example 2, player 2 (o) has lost against a good player 1 (x). Player 1's second move would be bottom left, forcing player 2 into middle left; player 1 then goes bottom right giving two options for a win (centre or bottom middle). You are therefore not showing good strategy for player 2!
AndyT
CC BY-SA 3.0
2017-03-22T08:00:52.817Z
2018-02-17T19:23:57.297Z
2018-02-17T19:23:57.297Z
user20160
<p>The assumptions here are that your opponent will block whenever you could win on the next move, and also that given the opportunity to force a win (by creating two different directions with two in a row) your opponent will take it, but that otherwise, your opponent's moves are random.</p>

<p>In that setting, your best strategy if you go first appears to be (1st move) take the center, (2nd move) move opposite your opponent, (3rd move) create two directions of two in a row (which will always be possibly unless your opponents first two moves were corners, in which case the game will tie - this is even true if your 3rd move is actually blocking - blocking will create a forced win for you). </p>

<p>What is your best strategy if you go second instead? Is there an opening move your opponent can make which would allow you, as second player, to force a win, instead of just a tie?</p>

CC BY-SA 3.0
2014-12-22T21:12:03.207Z
That strategy for an opponent seems a little strange to me. A more realistic strategy would be to try, in order of priority to: (1) make a move if it wins immediately, (2) block a win on the next turn, (3) do a fork.
Hao Ye
CC BY-SA 3.0
2014-12-22T23:36:57.810Z
Simple second player strategy on first move - Don't take a side square. Ironically, this is also the winning First player strategy on first move.
Forget I was ever here
CC BY-SA 3.0
2014-12-22T23:43:17.060Z
After that for both players: Win if you can; block if you must; or fork if you can.
Forget I was ever here
CC BY-SA 3.0
2018-02-01T14:57:28.810Z
"A strange game. The only winning move is not to play." ~ WOPR
Andrew
CC BY-SA 3.0
2018-02-11T01:48:03.530Z
Have your children learned [Nim](https://en.wikipedia.org/wiki/Nim) yet?
Forget I was ever here
<tic-tac-toe>
Is there a good tic tac toe strategy for the second player?
John Robertson
# Is there a good tic tac toe strategy for the second player?

(Asked by: username_0 on 2014-12-22)

The assumptions username_2 are that your opponent will block whenever you could win on the next move, and also that given the opportunity to force a win (by creating two different directions with two in a row) your opponent will take it, but that otherwise, your opponent's moves are random.

In that setting, your best strategy if you go first appears to be (1st move) take the center, (2nd move) move opposite your opponent, (3rd move) create two directions of two in a row (which will always be possibly unless your opponents first two moves were corners, in which case the game will tie - this is even true if your 3rd move is actually blocking - blocking will create a forced win for you).

What is your best strategy if you go second instead? Is there an opening move your opponent can make which would allow you, as second player, to force a win, instead of just a tie?

**Tags:** tic-tac-toe

> **Comments:**
> **username_1**: That strategy for an opponent seems a little strange to me. A more realistic strategy would be to try, in order of priority to: (1) make a move if it wins immediately, (2) block a win on the next turn, (3) do a fork.  
> **username_2**: Simple second player strategy on first move - Don't take a side square. Ironically, this is also the winning First player strategy on first move.  
> **username_2**: After that for both players: Win if you can; block if you must; or fork if you can.  
> **username_3**: "A strange game. The only winning move is not to play." ~ WOPR  
> **username_2**: Have your children learned [Nim](https://en.wikipedia.org/wiki/Nim) yet?  

---

## 2 answers

### Answer by username_4 on 2014-12-23. Score: 10

As you know, tic tac toe is a solved game that end in a tie with optimal play. And it's too short to really get any initiative as the second player, even for children. Going second there is no way to *force* a win without 2 misplays from the first player. So if you want a "strategy" for player 2, it really comes down to just not losing.

As for going first, I often liked taking a corner first because it offers more opportunities for my opponent to mess up (any square but the middle is a win for the first player with perfect play).

> **Comments:**
> **username_5**: XKCD have a nice [graphical representation of perfect play](https://xkcd.com/832/) for both first and second player - you can add the link/image to the answer  

---

### Answer by username_6 on 2017-03-22. Score: -1

If you are second, you will tie or lose automatically, unless your opponent is severely distracted or lets you win. In the following examples of moves and your responses, X moves first and each column is a set of two turns.

Example 1.

```
x o - | x o - | x o -
- - - | - o - | - o -
- - - | - - x | o x x

```

Example 2.

```
x - o | x - o | x - o
- - - | - x - | o x x
- - - | - - o | - - o

```

Example 3.

```
x - - | x - - | x x o
- o - | - o - | - o -
- - - | - o x | - o x

```

Example 4.

```
- x - | - x o | - x o
- o - | - o - | - o -
- - - | - - x | x o x

```

Example 5.

```
- x o | - x o | - x o
- - - | - x - | x x o
- - - | - o - | - o -

```

Example 6.

```
- x - | x x o | x x o
- - - | - - - | - o -
- o - | - o - | x o -

```

Example 7.

```
- - o | x - o | x - o
- x - | - x - | o x x
- - - | - - o | - - o

```

> **Comments:**
> **username_7**: I tried to salvage the post as good as it gets, however I still have to downvote it because I'm not sure what they're trying to say (whether it's supposed to be best practice, examples of turns that won't lose you the game, or simply examples of turns you could take). At least it should be somewhat readable now...  
> **username_8**: The answer seems much more legible like this -- I'm going to do a bit more editing.  
> **username_9**: In your example 2, player 2 (o) has lost against a good player 1 (x). Player 1's second move would be bottom left, forcing player 2 into middle left; player 1 then goes bottom right giving two options for a win (centre or bottom middle). You are therefore not showing good strategy for player 2!  

---

