Ever since the Chip's scan revealed a Second Level Wraith in the ruins, Green had not dared release any Mental Power. He had stayed sprawled on the ground, playing dead.
But judging by the Spirit Bodies' movements, Green had also realized that they seemed to still obey the rules left behind by the Wizard Organization. Unless something else happened, these Wraiths could not leave the areas they guarded.
Yaxi must have entered a high-risk area of the ruins and run into a powerful Spirit! That's why he ended up like this! Green analyzed silently.
At that thought, Green could not help feeling fortunate. He had only visited low-risk areas. Even the Library, the one place under tight Protection, relied chiefly on a Formation, which had completely lost its effectiveness with the passage of time.
The battle raged on. As the Skeleton Soldiers wore them down, one group of Wraiths replaced another, and both sides suffered losses.
The moon traveled across the sky. Beneath its light, Skeleton Soldier remains piled up like mountains, leaving the entire battlefield impossibly crowded. After a full thirteen hours, the moon was finally about to set.
The night sky gradually paled. Negative Energy stopped seeping from the ground, and the concentration of Negative-Energy Particles began to fall.
Green looked toward the battlefield. As the concentration of Negative-Energy Particles dropped, the Skeleton Soldiers' movements slowed, and even their strength waned considerably. Creatures like them depended heavily on their environment.
When the Negative-Energy Particles fell below a threshold, all the Skeleton Soldiers turned and headed back toward the sea. As they retreated, Green clearly saw the Wraiths guarding the ruins show humanlike relief, even a trace of joy on their faces.
With the first ray of sunlight, every Wraith and skeleton withdrew to its own domain. The Wraiths