
Just before the author signs off with "a friend" on the S.L.A letter, he highlights the word "Kill" at the foot of the letter, referencing Old Norse. In the identical position at the foot of the Exorcist letter the author highlights the strange characters in bold marker, before signing off with Me-37. Was the author of the S.L.A letter telling us that the word "Kill" could be decoded in the Exorcist letter characters, thereby confirming they were the author of both? The author of the S.L.A letter would not only have to know that characters existed at the foot of the Exorcist letter, because the San Francisco Chronicle had whitewashed them, but also know that they could possibly feature the word "Kill". Could the author of the S.L.A letter, if different from the author of the Exorcist letter, accidentally place the word "Kill" in the same position through two letters, and highlight them both in bold writing and quotation marks to signify their importance?
The San Francisco Chronicle, along with law enforcement seemingly didn't make the connection, because it wasn't until a few years ago that Zodiac researcher Kevin Robert Brooks offered up a possible solution to the Asian-style characters. When rearranged they were the perfect continuation to the author's preceding paragraph.

Was this the focus behind the entire S.L.A letter, using the Symbionese Liberation Army and "sla" as a precursor to providing the word "Kill" to the San Francisco Chronicle and law enforcement, and therefore verifying they were also responsible for the Exorcist letter? It seemed very fortunate that the word "Kill" in quotation marks was able to be formed by the Asian-style characters of the Exorcist letter, especially considering it was completely whitewashed from publication in the Chronicle.
If the Symbionese Liberation Army were responsible for the February 3rd 1974 S.L.A letter, then what are the chances they created the Exorcist letter too? - fashioned by weaving together traits of old Zodiac Killer letters such as the July 31st 1969 trinity and the Little List letter of July 26th 1970. Or did the Zodiac Killer simply strike gold, writing a letter about the Symbionese Liberation Army just one day before Patricia Hearst's kidnapping?
There is another intriguing possibility albeit without foundation. The Zodiac Killer stopped his letter writing sometime in 1971, with his campaign of terror having probably run its course. What are the chances he pursued different avenues in life, before joining the Symbionese Liberation Army, or becoming affiliated with them in some capacity by the turn of 1974. He then fires off a quartet of diluted Zodiac letters under the umbrella of his new found affiliation. The Symbionese Liberation Army's notable year was 1974, responsible for the Patricia Hearst kidnapping, the raid on the Hibernia Bank and the May 17th deadly shootout in Los Angeles, where six members were shot or burnt to death at 1466 East 54th Street after a standoff with the Los Angeles Police Department. The third letter of the quartet was the 'Badlands' card stating "In light of recent events, this kind of murder-glorification can only be deplorable at best (not that glorification of violence was ever justifiable)", mailed one week before the shootout. Subsequent to the shootout only one more communication would arrive in 1974 - the Red Phantom letter of July 8th 1974 - then radio silence. No correspondence subsequent to 1974 would ever be attributed as genuine Zodiac material.