Book of Heavens

The Book of Heavens is an ancient text in the lore of Dota 2.

History
Centuries ago, the great Book of Heavens was written by the aesthetes of Keyturn. These aesthetes were astronomers—they studied the wheeling of celestial bodies in the skies and recorded their arrangements in the Book of Heavens. From these observations, they managed to create what appears to be the first instance of timekeeping in the history of Dota 2's lore, counting the number of days in each season and calculating the day of the longest night.

Throughout their long study of the aethereal from their mundane vantage, they soon learned of a great cycle within the cycle that they studied. Among the many solstices, there was one called Wraith-Night, which was heralded by the green aurora blazes in the sky and the diminishing of the barrier between the planes, causing an influx of Wraith Essence to seep into the natural world—charging the wildlife with this essence and raising the dead from their sleep. The aesthetes of Keyturned were destroyed, and only the fragments of the Book of Heavens remained to preserve their existence from the ravages of oblivion.

Contents
This ancient book once contained the recorded movements and arrangements of celestial bodies in the skies. Now that the book (as well as its authors) has been destroyed and lost to history, only mere remnants of its passages remain. Thanks to the efforts of those who have copied its fragments, the memory of this book has survived to the present day, but the rest of its vast valuable knowledge is lost to us forever.