"The coast is clear. Come on." Rathgar motioned his companions through the door.
"Not good!" Feris whispered as he looked through the secret door. The chamber was dark but for Allianora's lamp. A rough bed of furs sat in one corner, and carved skulls adorned the walls. All sorts of creatures were represented, but goblin skulls were most common. "We need to get out of here."
"It's just goblins." Nimble shrugged. "What's the big deal?"
"This is a goblin wizard's den. A powerful one."
"Like Nimble said, it's just goblins." Rathgar said, poking around the skulls.
"Do you see those two dragon skulls?" Feris pointed to the place of honor among the collection. "Powerful magics. Let's go back."
"So let's take the skulls, and get out of here." Nimble suggested, reaching for the closest of the dragon skulls.
Not everyone uses paper, vellum, or papyrus to write things down on. Goblins, for instance, aren't known to use anything even resembling paper. The closest they get is inking skins. Sometimes the victim of the inking isn't dead when they begin. Rarely do they survive.
However, when goblin's really want something preserved, they carve it onto bones. Skulls are highly prized by the goblin shamans and wokans to scribe their spells upon. The more powerful the spell, the greater the creature. Any humanoid skull will serve for a cantrip, but for truly powerful magics, the skulls of creature like wargs, drakes, and minotaurs are used. Dragon skulls are used for the greatest of spells.
These spell skulls are normally used as a spell book, but in dire circumstances they can be employed as a scroll. However, like standard scrolls, when used the magic is used up, and the skull will disintegrate. Thus it is rare to see them used this way.