The first piece of invisible content is not actually invisible. Instead, on the first page of the actual Scout manual, the following words have been circled:
TOUCH THE CIRCLE
Touching the circle on the frontispiece (the "O" in "DON'T") turns the whole page into a light glyph, as noted above. The same applies for any of the Os in the back of the book as well. There are instructions towards the back detailing how to replace the frontispiece by using a page from another manual.
Reading the book under the light provided by a glyph lights up an array of colors in the book, all written in inks that are not visible otherwise. There seem to be five main colors, each associated with A one letter sign-off (and, apparently, a different speaker):
A - Red. A lively speaker with scratchy, cramped handwriting. His entries focus on relationships primarily. B - Orange. A terse speaker; all of his comments directly relate to escape attempts or glyph magic. Seems to be as much of a leader as this kind of setup allows. C - Yellow. The voice most likely to play devil's advocate on Belos's behalf. Has a lot of handwritten fights with B. F - Indigo. A soft, concerned voice that has a lot of practical tips, including lists of "allergies." H - Magenta. A rare voice compared to the others, with most of his notes showing up towards the end. Most of his comments are questions with no answers, or instructions where he answers himself later on.
INVISIBLE CONTENT - GUARDS
TOUCH THE CIRCLE
Touching the circle on the frontispiece (the "O" in "DON'T") turns the whole page into a light glyph, as noted above. The same applies for any of the Os in the back of the book as well. There are instructions towards the back detailing how to replace the frontispiece by using a page from another manual.
Reading the book under the light provided by a glyph lights up an array of colors in the book, all written in inks that are not visible otherwise. There seem to be five main colors, each associated with A one letter sign-off (and, apparently, a different speaker):
A - Red. A lively speaker with scratchy, cramped handwriting. His entries focus on relationships primarily.
B - Orange. A terse speaker; all of his comments directly relate to escape attempts or glyph magic. Seems to be as much of a leader as this kind of setup allows.
C - Yellow. The voice most likely to play devil's advocate on Belos's behalf. Has a lot of handwritten fights with B.
F - Indigo. A soft, concerned voice that has a lot of practical tips, including lists of "allergies."
H - Magenta. A rare voice compared to the others, with most of his notes showing up towards the end. Most of his comments are questions with no answers, or instructions where he answers himself later on.
There are no entries made by D, E, or G.