The December 7th 1969 cipher of 38 characters was the beginning of many short and apparently unsolvable codes. The sheer fact that he mailed the Z38, Z9, Z13 and Z32, comprising of no more than 92 characters in total, should have set off the alarm bells that these codes were nothing more than a message only understood to their designer without further input. That further input began only 29 days after the mailing of the "340" cipher with the wording of "paradice" and "slaves", gleaned from the 408 cipher of "the best part of it is that when I die I will be reborn in paradise and all the (people) I have killed will become my slaves" - and would play an integral part in the Z38 and Z9 codes, as they did in the superficial design of the November 8th 1969 "340" cipher and the configuration on the October 27th 1970 Halloween card. The chosen phraseology of "paradice and slaves" long preceded the Halloween card and the presumed Tim Holt comic book connection.
The fact that the December 7th 1969 and December 16th 1969 letters came within nine days of one another, separated by 29 days from the 340 cipher, facilitates an argument based on their limited characters, that these two Fairfield codes contained clues to the workings of the 340 cipher and therefore carried the same purpose. If we remove 14 characters (paradice, slaves) from the total of the Z38 code, we would have 24 characters remaining (by fire, by rope, by knife, by gun). Those 14 characters present at the base of the Z38, separated into rows of 6 and 8 characters (paradice, slaves). The others rows conveniently accommodating the remainder of the Halloween card phrase of by fire, by rope, by knife and by gun.
This interwoven pattern traversing the four communications of November 8th 1969, December 7th 1969, December 16th 1969 and October 27th 1970 will still be categorized under the category of unproven and likely unintentional. Short of a cryptographic solution to the 340 cipher, approaches to the codes such as the one presented here, will always be discarded and casually dismissed under the banner of "seeing patterns in the clouds" - thereby making any non-cryptographic solution to these codes and ciphers a non-starter. This means, that if the Zodiac Killer created a puzzle rather than a cryptogram, you will never be able to prove the case. Therefore, I have just wasted my time writing this article.