Mysterious pages are pages of the strange hallowed tome that can be obtained from looting any coffin within the Hallowed Sepulchre. There are five pages in total, one for each floor, with a 10% chance of being obtained provided that the player hasn't already obtained one. The collection log tracks which pages have been obtained.
The pages can be added into the strange hallowed tome, which is obtained by investigating the skeleton in the south-west corner of the minigame lobby.
If lost, the tome can be re-obtained from the skeleton with all previously added pages still present.
- ^ Jagex. Mod Husky's Twitter account. 18 June 2020. (Archived from the original on 18 June 2020.) Mod Husky: "Well, it's my birthday tomorrow and scuffed flames appear to be fixed so I'm in a good mood. As a result here's the ever so requested droprates from the sepulchre put together nicely on these images by @JagexRy"