Pillar 7

Pillar 7 is the shortest pillar. It also explains the method it uses to encrypt the alphabetic text. It is presumably a pillar to introduce participants to the concepts of encryption.

It contains an unexplained numerical grid near the top of the pillar.

Numerical Grid

The numerical grid on Pillar 7

At the top of the pillar is a grid of numbers of 5 rows and 26 columns. A triangular glyph surrounds a number (rather than pointing as in other pillars).

35248614916353547101490974 24725391509414892533731941 14909573522681490367353636 41635353213194116435346709 81491040353180149092635377

Transposition (Caesar) cipher

The remainder of the pillar is filled with a simple cipher - the Caesar cipher.

At the top is a plaintext which makes an obvious reference to Caesar:

A LETTER SHIFT A CIPHER MAKES A FAMOUS ROMANS NAME IT TAKES

Then below that, it pictorially depicts a letter shift. In this example, A>B, B>C, C>D and so on, with Z>A.

Below this is a cipher text:

B MFUUFS TIJGU B DJQIFS NBLFT B GBNPVT SPNBOT OBNF JU UBLFT C UJKHV QH VYQ AQW PQY ECP DTGCM DWV QVJGT OQXGU C EQFG ECP OCMG KRZHYHU WKHB EH VZDSSHG DERXW D NXID PDQ FRXOG ILQG WKHP RXW RPKR QMWJZZKRG WYMABY INGY PZBZIE XROZA OPK RNQV SA ENMPL XVZIZ GBHV ERIQIF

Using a simple online Caeser cipher calculator, this decrypts using various shifts to read

(With a shift of 1) A LETTER SHIFT A CIPHER MAKES A FAMOUS ROMANS NAME IT TAKES (With a shift of 2) A SHIFT OF TWO YOU NOW CAN BREAK BUT OTHER MOVES A CODE CAN MAKE (With a shift of 3) HOWEVER THEY BE SWAPPED ABOUT A KUFA MAN COULD FIND THEM OUT

The presence of the word "KUFA" is strange, but I confirmed that NXID appears in the cipher text.

The final four lines resist any number of simple shifts. It is possible that it is encoded using something like a Vigenere cipher.

An analysis using an online Vigenere breaking tool conducts frequency analysis to try to determine a key. It responds with a lot that start with "VIG", leading me to guess "VIGENERE".

(Using the Vigenere cipher with a key of "vigenere"): WHEN DIFFERENT SHIFTS EACH LETTER TAKES (and resetting at the end of the two lines) THE NAME OF WHICH GREAT CODE AWAKES

Base

A string of numbers runs around the base.

10 11 9 11 9 12 13 17 28 29 15 17 11 12 11 12 11 13 20 24 9 13 11 11 7 93 11 11 14 17