An acrostic is an arrangement of text (usually a poem or word list) where one letter (usually the initial letter) from each line, taken in order, spells out a secret message (usually one word or a short phrase).
Acrostics belong to the family of puzzles called wordplay. Authors of interactive fiction sometimes use acrostics to hide magic words or passwords which the player must discover. Less often, the secret message revealed by an acrostic might be used as a conversation topic or a topic to look up in a reference book. Long acrostics might conceivably spell out a command to use or an instruction to follow. Or maybe the message is just an easter egg for the player to find for the fun of it.
Commandment #12592 Oh ye who go about saying unto each other: "Hello sailor"; Dost thou know the magnitude of thy sin before the gods? Yea, verily, thou shalt be ground between two stones. Shall the angry gods cast thy body into the whirlpool? Surely, thy eye shall be put out with a sharp stick! Even unto the ends of the earth shalt thou wander and unto the land of the dead shalt thou be sent at last. Surely thou shalt repent of thy cunning.
Note that the first letters of each line spell out the name "ODYSSEUS". You can be sure that that word is useful somewhere in the game.
Usually the first letter of each line is used in spelling out the secret word or phrase, but not always. Acrostics might target the second, third, or terminal letters of each line instead. Diagonal acrostics are also possible by taking the nth letter of the nth line; e.g.: the first letter of the first line, then the second letter of the second line, and so on. An acrostic that uses both the initial and terminal letters of each line might be called a "double acrostic".
Note that standard acrostics that use initial letters are often completely unclued by authors. Players are therefore advised to be suspicious of all poems and word lists they encounter within IF, in case there is an acrostic message hidden within it.
However, authors who wish to use non-standard forms of the acrostic should hint somewhere in their games that such wordplay is possible, so players know that they need to examine text more carefully or in a particular way.
Font style hinting
Authors may sometimes be kind and use boldface or a different text color on the special letters, to make the acrostic easier to spot. (Note that this technique can also be used for secret messages that are not acrostics by simply marking up seemingly arbitrary letters in a larger message in a visually different style.)
Perhaps the secret message is backwards, and needs to be read upwards instead of downwards. This trick might make an acrostic slightly less obvious.
It's less easy to spot an acrostic if the secret message isn't presented in a ready-made column. For example, an initialism formed by taking the the first letters of the words in a sentence might be a way of doing a kind of acrostic.
Some assembly required
Authors can ramp up the difficulty of an acrostic by splitting up the lines onto different objects, such as pages in a diary. Players must seek out these objects and put them back into the correct order before the secret message can be determined. In this variation, it is important to make sure there's a clear ordering to the individual items that bear parts of the acrostic.
Perhaps an acrostic's secret message can be made by selecting the first words of each line instead of the letters. This variant might be considered if the secret message needs to be a full sentence instead of just one or two words.
- Initialism: A word formed from the initial letters of a phrase, and used as an abbreviation or short form of that phrase. For example, "LASER" is an initialism of Light Amplification by Stimulated Emission of Radiation.
- Mnemonic: A phrase or sentence that helps you remember something else. Often, a mnemonic's initial letters are the key to remembering a list of other things with the same initial letters.