|This is one of my favorite pencil-and-paper "parlor games;"
a game I've played with all of my friends for the last fifteen years or
so. Almost all of my really good gaming pals have sat up with me in the
small hours of the morning, usually in a Denny's
or donut shop or some other late-night dining spot, cursing over difficult
letters and begging the waitress for pencils.
5x5 ("Five by Five," or simply "25" or
even "LSD" when I'm feeling obscure) is a logical guessing game,
a cousin of both hangman and Mastermind. I didn't invent this game – I
first discovered it in a book of games and puzzles when I was in elementary
school. I think the book was a little red paperback called Games for
the Superintelligent, by Jim Fixx (the clever chap who started the
jogging craze, and later fell dead of a heart attack while jogging), but
since I haven't seen the book in over a decade, I could be dreaming it.
The rules here are expanded and clarified from the version I learned years
Anyway, here's the game. It's simple, sometimes maddening, and always diverting.
Go grab a friend and try it out.
Each player needs a pencil and a piece of paper.
Small note-paper is sufficient, usually, unless you write really big. It
helps if each player writes the alphabet at the top of his paper – it's
useful for keeping track of your progress. Before beginning play, each
player must secretly choose and record a word. The word must conform to
the following three rules:
- The word must be "Scrabble
Legal" – the standard set of rules for word games. This means an English
word with no capital letters, no hyphens or apostrophes or other forms
of punctuation, no funny stuff. An ordinary, vanilla word. There are millions
of them to choose from, so this isn't much of a restriction.
- The word must be five letters long.
- The word must contain five different
letters. So, "BEGIN" is a legal word, but "START" is
not, since START has only four distinct letters: S, T, A and R.
You must choose a word which you are certain your opponent
will be familiar with. 5×5 is a logic race; it's not fair (or very
interesting) to win it by choosing obscure words. Usually, very common
words are the trickiest to guess, anyway – the best words are those with
plenty of common letters to confuse the guesser.
Pick who goes first by fiat or by flipping
a coin – it doesn't really matter; there is no particular advantage to
going first (in fact, some prefer to go second, although there's technically
no advantage to that, either).
On your turn, you must make a guess. This guess is another five-letter
word, and it must also be "Scrabble Legal." However, it can include
duplicate letters. The traditional first-guess words are START, BEGIN,
and FIRST, but it can be any legal word you like.
Write your guess down. You'll want to keep a list of both your guesses
and your opponents, in two separate columns.
Your opponent, after writing down your guess on his own sheet, gives you
a number from 0 to 5. This is the number of letters that your guess has
in common with his secret word. Mastermind players take note:
The number has nothing to do with the position of the correct letters.
Note that STARE and START share only 4 letters in common; the additional
"T" in the guess START is simply ignored. Repeated letters can
thus be used strategically to help eliminate or pin down particular letters.
Play continues in this way, each player guessing and responding, until
somebody correctly guesses his opponent's word. Each player gets the same
number of guesses, so if player One wins on his 10th guess,
player two still gets his 10th guess, making tie games possible.
It will sometimes happen that a player realizes,
deep into the game, that he has miscounted on one of his previous answers,
and that his opponent is therefore playing with false information! When
this happens, the "Error Rules" immediately come into play –
the game is frozen until the Error has been corrected thus:
First, the player who made the mistake must correct it. Second, he must
immediately grant a number of free "bonus" guesses to his opponent.
These guesses are outside the structure of the normal game, and don't count
as turns for the opponent. The number of free guesses awarded is equal
to half the guesses the player has made since being given the false information,
rounded up. So, if he hasn't made any guesses since the error, he gets
no free guesses at all. If he has made 7 guesses since the error, he gets
4 guesses as his bonus, and so on. After the "penalty shots"
have been taken, the game resumes.
When going from guess to guess, work in small,
incremental changes from your previous guesses. If START got you a response
of 2, and STARE gets you a response of 3, then you've got the E for sure.
If you change more than one letter, the results will require extra, valuable
turns to interpret.
Once you've eliminated some letters, you can use these "dead"
letters to build words to test your theories. For instance, if you've eliminated
C, G, H, I, K, N, P, R, T, and V, and know for sure that either A or E
is in your foe's word, but aren't sure which, you can guess GRANT. Since
you've already eliminated G, R, N and T, you know the response will be
either 1 or 0. If it's 1, then you've got the A and eliminated the E. If
it's zero, then vice-versa!
Once you've advanced in skill a bit, you'll find that knowing that either
the A and E are in the word is often good enough . . . Rather than wasting
a turn now to determine which, just mark the "suspect pair" and
get back to it later if you need to. In the meantime, work on the other
letters – having pairs can often lead to intuitive leaps that can win you
On average, a skilled 5×5 player will guess his foe's word on the
10th or 11th guess – quicker than that is very good, and too much slower
than that will make you shark-bait for the experts! A well-chosen secret
word, of course, can make a difference of a turn or two, and that's all
the difference in the world, in 5×5.
While any old notepaper will do, I've prepared
a handy 5×5 Sheet, in Adobe Acrobat (PDF) format (in a 7k
downloadable ZIP), for those who like to print out reams of stuff.
It has space at the top so you can fold a flap down for privacy (essential
when playing across the table at Denny's), a big box for your word, five
smaller boxes for the letters in your foe's word (as you deduce them) a
handy alphabet (in case you forget how it goes) and dividing lines.