Solution: Writing Complementary Characters

Answer: OX, PI

Written by Amos Eshel

This puzzle is composed of 13 mini-puzzles based on pairs of unique letters of the alphabet, with the only other element being hyphen-like lines. Some pairs have a single mini-puzzle producing 2 letters, while others have 2 separate components that work the same way and provide a letter each. This allows a letter to be assigned to each letter of the alphabet which provides a pair of phrases for final extraction of the two aptly two-letter answers to this puzzle.

PI - PRIVATE EYE ABBR    BUNYANS BEAST - OXABCDEFG HIJ KLMN    OPQRSTU VWXYZ

In many mini-puzzles, - & = are used to represent the 1st & 2nd letter to extract respectively, where 1st & 2nd are assigned to the alphabet letters based on the ordering of the letters to match the mini-puzzle type, e.g., the YO puzzle is composed of YO-YO tricks, so - is assigned to Y and = to O.

The left side of the puzzle is split into an upper section and a lower one. The upper section is positive examples of the logic for a few puzzles, that is things which are valid. The lower section is versions that break the rule of the respective puzzle, indicated by the lower case letters in use, e.g. i > II is not valid because 1 is not greater than 2.

AZ – PT – Alpha & Zulu
The provided blanks match the NATO Alphabet starting at ALPHA, ending in ZULU and going through PAPA & TANGO.
ALPHA
 |
PAPA
 |
TANGO
 |
ZULU

BW – RE – Black & White
These are Yin Yang logic puzzles. The W’s form the shape of an E on the left, and the B’s form the shape of an R on the right.

CH – IE – Carbon & Hydrogen
The provided representations are of two hydrocarbon molecules. The smaller one is ETHANE and has the H’s bolded to indicate the extracted letter is assigned to H. The larger one is ISOBUTANE and similarly has the C’s bolded.

DJ – VE – Disc Jockey
Unlike the other puzzles, this one is blue, because it’s a hyperlink to a song clip. The audio is the opening bars of I WILL SURVIVE.

EU – AS – European Union
The image is composed of the English names of countries in the European Union, with all of their E’s & U’s provided, with positions as they would be found on a map. The two countries in question (bolded and with a – / =) are AUSTRIA & SWEDEN.

FT – TN – False & True
These are collapsed truth tables, e.g. the table below is shown in the puzzle as TFFF. The example in the upper left section of the puzzle differentiates standard truth table ordering from standard logic gate ordering. Applying the specified transformations (twice) turns the F’s into TFTFF and T’s into FTTTF. Converting these to 1s & 0s and this 5-bit binary into letters gives the extraction.

KG – AE – Kilogram
Kilograms are one of the 7 SI Base Units. The provided diagram is the New SI diagram showing the dependency graph of the base units on fundamental constants of the universe.

IV – YB – Roman Numerals
This is a Futoshiki puzzle, a Latin square with some inequalities between cells. Solving it has the V outside the grid pointing at a 2 (=B) and the I outside the grid pointing at a 25 (=Y).

LN – BR – Natural Logarithm
This is the first 25 digits of the mathematical constant e, the base of the natural logarithm.

   2.7182818284590452353602874713  
   _._NN__NN_____________LL______

N: 18 (=R)
L: 02 (=B)

SP – AU – Spanish
The left side fits the colors ROYGBIV in English. The right side is the translation of these colors into Spanish. All instances of the letters S & P are provided (which happens to be none). Extract from AMARILLO and AZUL.

QR – NY – Quick Response Code
Convert all the Q’s to black squares, and the R’s to white squares to get a QR code which when scanned leads to an outline of the state of New York (abbreviated to NY).

XM – AB – XM Satellite Radio
The 36 XM’s correspond to channel 36 – ALT NATION
The 19 XM’s correspond to channel 19 – BOB MARLEY’S TUFF GONG RADIO

YO – SB – yoyo tricks
Two diagrams of yo-yo tricks are provided. One is ROCK THE BABY, the other the SLEEPER. The O’s represent the yo-yo itself, while the Y’s represent the string (with a direction). For Rock the Baby the movement of the yo-yo is represented by the –‘s; for the Sleeper the movement is represented by the different columns.