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2008 Edition of the
Online Guide to the Engima


Preface to the Guide
History of the NPL
Membership Information
Sharing the Puzzles
      Sharing the fun
      Combining Talents
Composing
Editorial Verses
Flats
      Acrostical Enigma
      Alternade
      Ambigram
      Anagram
      Antigram
      Apt. . .
      Backswitch
      Baltimore Deletion
      Baltimore Transdeletion
      Beheadment
      Bigram. . .
      Brookline Letter-Change
      Change of Heart
      Changeover
      Charade
      Combination Padlock
      Consonantcy
      Curtailment
      Deletion
      Diastichal Enigma
      Double-Cross
      Dropout
      Enigma
      Enigmatic Rebus
      False derivative
      FWNFR
      Group flat
      Head-to-Tail Shift
      Heart Transplant
      Heteronym
      Homoantonym
      Homoconcominym
      Homonym
      Homosynonym
      Interlock
      Letter Bank
      Letter Change
      Letter Shift
      Linkade
      Literatim
      Metathesis
      Mutation
      Mynoreteh
      Order Takeout
      Overloaded. . .
      Padlock
      Palindrome
      Phonetic. . .
      Phrase Shift
      Picture. . .
      Progressive. . .
      Rebade
      Rebus
      Redro takeout
      Repeated-Letter Change
      Repeated-Letter Deletion
      Reversal
      Reversed. . .
      Riddle
      Sound Change
      Sound Shift
      Spoonergram
      Subade
      Suber
      Switchback
      Telestichal Enigma
      Terminal Deletion
      Transaddition
      Transade
      Trans-Cross
      Transdeletion
      Transpogram
      Transposal
      Trigram. . .
      Welded. . .
      Word Deletion
      Word Substitution
      Solving the Rebus
      Browse the Flat Pages
Introduction to Forms
      From A to O
      From P to Z
      Form Modifiers
Cryptograms
      Constructing Medium Crypts
      Solving Cryptograms
      Other Solving Approaches
Extras
      Solving Cryptics
      Composing Cryptics
      Observations
Reference Books
Constitution
      Bylaws
Glossary
Supplements
      Non-Guide Flats
      Non-Guide Forms
      Non-Guide Extras
      Where to Find It
      Form Notation
      Italian Picture Puzzles
      Abbreviated Guide to Flats
      Mobile Guide to Flats
      Submissions
Errata


© Copyright 2013 by
the National Puzzlers' League
 BIGRAM . . .

Bigram forms have two letters per space rather than the usual one. See the example in the square description.

 COMPOUND . . .

Compound forms consist of a number of connected forms that combine to make one larger shape. The chevron star and Rokeby star are examples of compound forms.

 CONNECTED . . .

Connected forms consist of two separate forms that share a common side-for example, a pyramid and an inverted pyramid with the same baseword. See the examples in the square and pyramid descriptions.

 CRYPTIC . . .

A standard form of any type with clues given in cryptic-crossword style is a cryptic form. Cryptic forms have appeared in both the Forms and Extras sections of The Enigma.

 DOUBLE . . .

Most forms have the same words across and down. Forms whose across words are different from the down words are called “double forms.” When a square, for example, has different words across and down, it is termed a “double square.” (Forms that inherently have different words across and down, such as pyramids, are not called double.) Double forms are harder to create than standard forms. See the examples in the diamond and square descriptions; other shapes shown in this Guide as single can also be constructed as double.

 HOLLOW . . .

A hollow form has the same shape as the usual example of that form, but with a small section missing from the middle. The missing section is a smaller version of the form’s shape. Hollow forms have several lines that contain more than one word. See the example in the diamond description.

 INVERTED . . .

In inverted forms, such as inverted pyramids and halfsquares, the shortest word appears at the bottom of the form. See the word after “inverted” in the title for an example.

 LEFT / RIGHT . . .

For forms that can be created in various orientations, such as halfsquares and enneagons, “left” and “right” describe which way the words slant. In left forms, the words appear to flow from top left to bottom right; in right forms, they flow from top right to bottom left. See the word after “left” or “right” in the title for an example.

 PROGRESSIVE . . .

Usually seen as squares, progressive forms consist of successive words that differ by only one letter. The first word is beheaded and has a new letter added to its end to make the second word, and so on throughout the form. See the example in the square description.

 SEQUENTIAL . . .

Usually seen as squares, all the forms in a sequential set contain a certain word, which will be seen as the first word in the first form, the second word in the second form, and so on until it has appeared in each position once. See the example in the square description.

 SOMETHING DIFFERENT . . .

Something Different forms are described in the Extras section of the Guide.

 TRIGRAM . . .

Trigram forms have three letters per space rather than the usual one. See the example in the square description.

 TRUNCATED . . .

In a truncated pyramid or pyramid variation (such as a pyramidal windmill), the pyramid’s base is an even number of letters; thus, the shortest word is two letters long rather than one. See the example in the pyramid description.

 VARIOIGRAM . . .

In most forms, the solver fills in one letter per space. In a variogram form - most often a square - a space might contain just one letter, or might contain any number of letters more than that. Bigram and trigram forms are specific cases of a variogram form. See the example in the square description.

Variogram forms are often significantly harder than standard forms. Generally, it is best to clue them as straightforwardly as possible.

Formists sometimes compose variogram squares to incorporate some specific idea; for example, to include the sequence NPL in a number of places, or to have a pattern in the number of letters used in each space.

In a space where a word crosses itself-such as the first space in a square-having a long multiletter sequence can be problematic for solvers. Multiletter sequences should generally be included in two words.

 VOWELLESS / CONSONANTLESS . . .

In a vowelless form, the answers to the clues must have their vowels removed before they will fit in the shape; similarly for consonantless forms. In these forms, Y is always considered a vowel.

Because each answer provides less information to the solver than usual, it is best to clue the entries as straightforwardly as possible. The forms editor will sometimes provide extra information, such as enumerations for any phrases, or NI2/NI3 tags.

See the examples in the square description.