Let's start out with trying to build a pyramid. The D and the M on the left and right side seem to be a good base. However, upon further examination one notices that no matter how one tries, the letters just do not fit to make a good pyramid or triangle shape.
Either the right side does not fit.
Or the left side does not fit.
The ten letters will always form an odd man out situation when trying to stack the letters in a pyramid without a base shape.
However if the letters are instead placed in a full position the ten letter combination forms an equilateral triangle.
Since the D and the M are off to the far left and far right side of the monument inscription, then they must occupy the lower left and right circles. Since S is in the middle of the letters sequence it constitutes the top of the pyramid.
The next level of the pyramid has two circles. The occurence of two letters O in the inscription signify that the two O's should occupy these two circles.
The next level of the pyramid has three circles. The occurence of three letters V in the inscription signify that the three V's should occupy these three circles.
Two circles are left. Two letters are left U and A.
Or is it A and U? A and U it turns out will lead to an error.
U and A is the correct sequence to use in the decoder.
The deciphering mechanism consists of a mapping of previous and next letters in the alphabet. This mapping only applies to the edges of the triangle. Only these edges translate current letters with previous and next letters.
The left side of the pyramid has lower polarity (C<D and R<S). The right side of the pyramid has higher polarity (T>S and N>M). The bottom of the pyramid has reverse polarity (E<C and L>M).
The edges of the triangle can swap. Prev/Next letters that are adjacent before a swap must be adjacent after a swap. For example, C and R remain adjacent, E and L remain adjacent, and N and T remain adjacent before and after a swap. Above and below are two examples of a swap taking place.
