In this instance we have a trinity of coincidences, where the Zodiac Killer tempts us with a signature from the verse, from which we can form the sentence of "my name is", that he previously used in his April 20th 1970 letter as an introduction to a mystery 13 symbol code and his name.
The Exorcist letter broke with tradition when he used "Me" instead of his crosshairs as an identity, before giving us his running victim total. Bearing in mind the aforementioned correlation between the Exorcist letter and "My Name is" letter, I couldn't help thinking his identity of "Me" would be found in the 13 symbol code using an extremely simplistic method. There is little doubt that the Zodiac Killer knew a 13 character code could not be solved using conventional techniques because of its length, so very likely created something superficial. The fact that this letter was mailed with an AM postmark on the same day the Robert Salem murder broke in the morning edition of the San Francisco Chronicle, with the Zodiac pseudonym scrawled on the wall of the victim's apartment - likely meant that this letter was prepared in haste. A code created this quickly has a high probability of being solved - a code with one repetitive feature of three circled 8's. Using the shift technique the Zodiac Killer employed in the 340 cipher, solved by David Oranchak (USA), Sam Blake (Australia) and Jarl Van Eycke (Belgium) in 2020, I used a period 8 shift in the code to select new characters 8 places to the right.
Another communication, mailed on October 27th 1970, also featured a name synonymous with The Mikado, when the Zodiac Killer wrote *peek-a-boo you are doomed" around the knot-hole of a tree. Peek-a-boo was a character from an 1888 production of The Mikado, entitled The Capitalist. But take a look at the "ME" in the word doomed, in a card that stated "I feel it in my bones, you ache to know my name, and so I'll clue you in."