Ruined Spell Book
Spell books that weren't well-preserved, and now we can't know what was inside. Only repairing these books with the imbuement altar could help to restore the old knowledge.
Obtaining
You can obtain it by killing mobs (e.g., zombies, skeletons, and more) or just looting structures like library ruins, obelisks and some other vanilla structures.
Usage
First, you need to have an imbuement altar with 4 connected receptacles. Place it in the imbuement altar and fill the 4 receptacles connected with any spectral dust (this will determine the spell's element!) and then wait for the reparation process to finish.
