The Song created by the Seven after they Chained with Cosal, which they did after he completed his training and while he was being turned into the Will of the Planet that would serve as the core for the new Ra Ciela. This Song is used to create a new planet on the place where the old Ra Ciela used to be located, with similar physical characteristics to it. While this might seem pretty simple, it's actually a complicated process that requires several conditions to be accomplished successfully.