At the northern edge of Nälu, stands four pillars. Round orbs like giant pearls perch atop the pillars creating an invisible perimeter which holds back the evil that once poisoned the lives and lands of Nälu. Golden gryphons from Zohar are said to stand guard over the Manoa Stones. None who set eyes upon them and live except for their caretakers.
But where did the Manoa Stones come from?
Some say they came from the land beyond, a gift from Zohar. The merfolk claim their healing waters gave birth to them over a thousand years ago. But none since have appeared in their underwater garden.
In Secrets Kept, Headmaster and High Guardian Saeed sends Nerissa to inspect the Perimeter. And in Dragon Thief, the merfolk celebrate the Manoa Stones with much dancing and feasting, above water and beneath.
During the great battle of Raemoja, the unholy union between Stygian and Raezana was severed, yet the battle raged on. Stygian, even without the supernatural aid of Raezana, still had the Dwäza, and they were bent on destroying the Alliance.
Then the merfolk and their dragons appeared, bringing with them the four Manoa Stones. As the Alliance pushed their enemy north, the stones prohibited the enemy from regaining the ground they had lost. Pillars were later erected and the stones placed on top.
But the power of the Manoa Stones will not last forever. It will eventually weaken, and what then, will the Guardians do? But for now, the Perimeter remains strong and the Guardians have other problems on their hands, such as the Corrupted Dagger falling into the wrong hands.