The Nature of Darkness

Exploration Stage: Sun Pavilion
From: Yui
Description: The stars tell us about a dark presence that has enveloped the sun... If the wise monk intends to find out about the nature of this darkness, he will need a special item. Could you help me find the eternal knot? It's equipped with immeasurably superior properties!
Completed: You've found the eternal knot! It has mystical powers, and it contains enormous amounts of light energy. With its power, surely the monk will be able to discover the true nature of the darkness that has enveloped the sun. Once we know that, we will also know how we should fight our enemies.