A long time ago, it used to be common to travel between different worlds.

At first, such a practice was difficult. You could only travel to these places if you happened to find a conduit to Aestor, the forest between worlds. Such a chance was extremely rare, and even then, it was almost surely a one way trip.

Then one day, a small, nomadic race called the Luune had traveled to Aestor and found their way back. They came back with seeds of the trees in Aestor and planted it in their home world of Éloras. From those trees, they made paper, thread, wood, and ink: all of which they would use to make special books that would allow them to travel wherever they wished.

These books, called Conduit Tomes, were widely used for a long time. But after a while, they were slowly forgotten as people abandoned the slow rhythms of life. The craft and books became a relic of the past lost to time, and to this day only a few remain who know it.