Wyrd Runestones

Wyrd Runestones came from the aftermath of Wyrd's destruction when Nyx called upon the Dark Gods to aid her in his defeat. Wyrd's body shattered all over the world, forming into the Wyrd Runestone fragments from which his dream magics would be derived. This is where many practitioners of magic draw their power from. The Runestones were used by the Callieach and the Trow during the height of their existence. They were also used by necromancers such as Bahl'lal the Watcher.

GURPS Myth
Rune Stones are the original rune stones of Myth. These landmark-sized monoliths are thought to be fragments of the One Dream, barrows of the Callieach, or both. Their rough surfaces become reflective if an archmage taps them. Each apparently facilitates study and casting of a single dream, but archmages are extremely tight-lipped about any additional properties. Their locations are kept secret by those who know them.