Glass Bone is a very hard to find substance that can be taken from the Great Dream and has the property of “absorbing” strong emotional states.

The Halloween Party found a crate of these in the Cortijo de la Vara, where they had been acquired by a wealthy spanish occultist and were most probably the cause of his, his family's and his servant's death.

One was used by the Bowler-Hatted Man to actualize a Manifestation of Oblivion from the Great Dream, by telling a short story about some kind of eldritch deity.

The Bowler-Hatted Man said that these bones are the remains of almost forgotten dreams and memories leached of substance, meaning, and color, and they can only be found in a desert made of broken glass in the deepest reaches of the Great Dream.