Greg, proud survivor of an ant attack (and a pretty good guy)

A simple mystery puzzle. Mystery puzzles have no stated rules, and their answers are usually a word or short phrase. I suppose I am getting in gear for this year's MIT Mystery Hunt. Some spoilery discussion of this particular kind of mystery puzzle follows.

This is a rather basic example of what, in some puzzle construction circles, is referred to as an ISIS puzzle. ISIS is sort for its solving process,
  • Identify,
  • Sort,
  • Index and
  • Select.
Puzzles of this sort rely on some sort of large data set, and the "Identify" first step involves recognising the appropriate set. Consider the periodic table, or list of Tony award winners. Once you are inspired enough to recognise the data set in question, there is often considerable legwork in collecting the required information. Typically, you need more of a table than a list of information. For example, on a puzzle involving Tony winners, the year they won, the name of their play, and possibly information such as others in their year's short list, number of awards won by that particular author or play and so forth need be collected. As you can imagine, it is not always clear which information is relevant and which is not. In these cases, the puzzle's title and/or flavour text may hint towards the required information. In other cases, you have to rely on intuition, or just collect everything. Between given and collected data, you need at least three kinds of information:
  • Some form of text
  • Something which has a natural order. Years, baseball positions around the diamond, that sort of thing.
  • Some form of number.
Three is something of a bare minimum; more complex puzzles may find use for more.

Sort refers to ordering your data set in a particular way, according to some value with an obvious order. Index refers to using a numerical value extracting a substring (typically, a single letter) from related textual information. For example, indexing into"Taurus" using a related 4 would result in R.
Sort and index both rely on some sort of numerical value, either a given one, or one that is part of the data set. As you can imagine, this often creates confusion about which values to use for each purpose, and, in the case of sets with lots of associated values (the periodic table, baseball players), which to ignore. Typically, sorting values are not repeated, and the indexing values are smaller than the length of the associated text.

Select is the finishing step. Essentially, you read the indexed parts in the sorted order, and you end up with either the solution, or a clue to the solution. As with most mystery puzzles, the solution will tend to somehow be related to the subject matter, or verified by the flavour text provided. And a with most mystery puzzles, this rough outline of its mechanics will be fiddled with pretty often.

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