Daru

Daru is the oldest and largest tree on Arturia. Planted almost 35,000 years before Book 1 by Brahma from a cutting of a sessile oak tree from Heaven's Arcane Garden, Daru was the first of the Scions of Heaven to be planted. While the Nether Realm portal that used to be in Daru's roots is long gone, the roots reach far below the grounds of Castle Arturia where it is planted, extending down into the great Crystal Caverns, in which dwell the Black and White Dragons, both of which chew on Daru's roots. As Daru, like the other Scions of Heaven, has magical properties, the Black and White Dragons produce a healing elixir instead of venom that can be used to heal any injury, even reviving sentients from the brink of death. However, the substance is useless against illnesses.