Left list (2 letters each)
IW
JC, SL, AC
JT
MB, PT
?
8-letter main list first row
OVERLORD
?
THRILLED
CRANIUMS
?
VOLCANIC
?
second row
VOMITING
CROCHET
?
REAWAKEN
VOCALIZE
?
?
third row
?
PATOOTIE
SPOOKING
?
?
?
NUMEROUS
?
?
?
Codes attachment
Each of these can be decoded with the Caesar cipher -3 to reveal the keyword for the Vigenere ciphers in the other four episodes at the beginning of season 2.
ZLGGOH (WIDDLE), Scaryoke
VKLIWHU (SHIFTER), Into the Bunker
ZKDWHYV (WHATEVS), The Golf War
EHDUR (BEARO), Soos and the Real Girl
Speaking of Soos and the Real Girl, a Post-it note on Soos' computer says "Password: FIXINIT1." FIXINIT1 is also Soos's license plate number, as seen in Society of the Blind Eye. Note: Soos and Stan both have 8 characters on their license plate, but the legal limit in Oregon is 6.
Cryptogram in book
When decoded with the atbash cipher, it reads: "Pure energy, not skin and bone, rising like the Shepard tone." The Shepard tone is an auditory illusion where a tone seems to perpetually rise in pitch. In other words, it sounds like the sound is rising forever, but it's really not. My best guess is that this phrase describes Bill, who, as per his own admission, is a being of pure energy, and seems to be continually increasing his power, but in reality has limits.
My guesses
I have thought of a few more possible passwords that have eight characters:
STNLYMBL
MCGUCKET
MCGKNOWS
JOURNALS
STAN1982
VIGENERE
