Mysterious chronicle (part 7) is a book found only in Daemonheim. It may appear in front of the dungeon-ending ladder after killing the boss monster.
It was written in year 1337 of the Fourth Age. Bilrach ponders on the nature of the place, believing a magical force keeps changing the layout, referencing how no single dungeon layout is the same as another dungeon when Dungeoneering.
As the giants can no longer proceed through the human built tunnels, he decides to use them as a food source instead.
Year 1337 of the 4th Age:
The soil I tunnel through is like no other. Someone or something has created this place as some sort of safeguard. Sometimes, when I use my magic to carve through, the areas behind collapse and reappear elsewhere. There is some magical force at play here that is hard to comprehend. Recently, many of my servants were cut off - they said the dungeon I'd forged had a different layout from when they left.
On the topic of servants, they are more frail than I feared. The giants last longer, but they can no longer fit into the small tunnels their human counterparts dig. I'll just slay them all and use their meat to feed the other slaves. Hah! How I do amuse myself so!Zamorak be praised!