When the Zodiac Killer mailed the second Fairfield letter on December 16th 1969 he included a very short code of five characters, accompanied by his Zodiac crosshairs, with four smaller crosshairs in each quadrant. It has been noted by many Zodiac researchers that this configuration resembled the Halloween card design he mailed approximately ten months later, which contained the bisecting "paradice" and "slaves", with the wording By Fire, By Gun, By Rope and By Knife in each quadrant. The rudimentary design of the Fairfield letter with four small crosshairs could be representative of these four weapons. I used this premise to place the word "By" immediately preceding the larger crosshairs, above ciphertext characters 4 & 5 (see below).
The last time the Zodiac Killer demanded we print his cipher in the newspaper, he wrote to the San Francisco Examiner and threatened "I want you to print this cipher on the frunt page by Fry afternoon Aug 1-69. If you do not print this cipher, I will go on a kill rampage Fry night". To the San Francisco Chronicle he wrote "If you do not print this cipher by the afternoon of Fry.1st of Aug 69, I will go on a kill ram-Page Fry. night". To the Vallejo Times-Herald he wrote "I want you to print this cipher on your frunt page by Fry Afternoon Aug 1-69, If you do not do this I will go on a kill ram page Fry night that will last the whole week end". Every single time the Zodiac Killer demanded the newspaper print his cipher, he followed it up by using "Fry" to represent Friday (six times in total). Therefore, when he demanded his five character code be printed in the newspaper by stating "you better print", it could be reasoned that this sentence be completed to "you better print Fry". This satisfies the repeating ciphertext character at positions 3 & 5.
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