Divine nails are very large, typically broken, crystal pillars that can be found in ancient ruins across Teyvat. They have been seen to contain a lot of power and can even impact the Ley Lines (networks of elemental energy and memories of the whole word) of areas where they are located. According to legends, the divine nails were dropped to heal the lands after the war between the Heavenly Principles and the Second Who Came (Second Throne of Heavens-an unknown entity that fought with the Primordial One before the Archon war), suppressing secrets, forbidden knowledge, and the abyss. However the nails also heavily damage the areas they descended on. Nahida (Buer) does confirm that divine nails have the ability to purify and stabilize powers that don't come from Teyvat, such as the Forbidden Knowledge.
Despite the nails have the ability to purify powers that corrupt the world, it causes mass destruction. Dragonspine was once a lush mountain with an irminsul tree that the people revered, however with the descent of the Divine Nail, it shattered the irminsul tree and reversed the climate of the mountain to become a snowy wasteland.
For some reason, the divine nail is shattered when discovered by the Traveler. Most other divine nails seen however are intact, such as in the Chasm. The divine nail that descended there created an incredibly large crater and it later became known as the Chasm, where a civilization even older than Khaenri'ah was present.
The divine nail would spawn in the unique Lumenstones and Lumenspar and the physical structure of the mines began to shift and change like it was alive.
In Inazuma, Tsurumi island its civilization would also have a divine nail dropped on it and its power would mix with the Thunderbird's power, creating a fog with unique time-altering properties.
In Sumeru, another divine nail would be the reason for the desertification of the region. Because of the impact, Mt. Damavand would form but the power would also form a permanent tornado. In both Inazuma and Sumeru, the divine nail cannot be found, but
withered irminsul trees can be found in both locations. In Natlan, a divine nail can be seen within the Night Kingdom, suggesting that the creation of a divine nail may be the cause of the creation of the Night Kingdom.
Many players speculate that Divine Nails are representation of Celestia's anger of sorts. Many of these civilizations that were destroyed alongside the areas by the divine nails are seen as unique civilizations. Some were incredibly advanced and many of the others had diverged in some way from the laws of the Heavenly Principles. Some were also possibly destroyed for knowing too much about the Heavenly Principles. Regardless, many of these civilizations seems to have angered the Heavenly Principles in some way and were destroyed as a result of that.
Fun fact: Each divine nail in the different regions are called different things.
In Dragonspine, it is called the Skyfrost Nail, and in the Chasm, it's called the Spirtstone or Wishstone.
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