Instigated by Malvos, the wizard Nohr destroyed the tree trying to become a planeswalker. When it was destroyed, the stability of the plane was violated. The ancient curse of the god who created this plane became true. The isle broke into two halves, separating the Clan. Nohr and his descendants were cursed with madness.
As foretold by Haen, the Mending of the Clan Tree occurred when the lines of Haen and Nohr finally met. 520 years after the Parting, the Keeper Aylith used her powers to break the curse on Nazir. Together they spoke the litany of light and recreated the Clan Tree of Cridhe from the last existing acorn.