The underground lake was as still as a mirror, but the air around Oro, the Shell of Ages, hummed with an invisible energy. Kaito stood on the edge of the water, his boots soaking wet, looking up at the colossal turtle. The silver whistle felt warm in his hand, almost as if it were breathing.
"To find your father, you must first survive the Abyss," Oro's voice boomed inside Kaito's mind. "And to survive the Abyss, you must not fight the water. You must become it."
Kaito frowned. "Become the water? I'm a human, Oro. I'm a sailor, not a fish."
The giant turtle let out a sound that could only be described as a deep, watery chuckle. "Even a sailor must know the heart of the wave. Close your eyes, Tide-Walker. Hold your compass and the whistle. Now, listen."
Kaito did as he was told. At first, he heard nothing but the slow drip-drip of water from the cave ceiling. But as he focused, the sound changed. He began to hear a heartbeat—not his own, but something much deeper and slower. It was the rhythm of the ocean itself, pushing and pulling against the shores of the world.
"The sea has a memory," Oro continued. "It remembers every ship that sank, every treasure lost, and every hero who dared to cross it. Your compass reacts to that memory. Use it."
Suddenly, Kaito felt a surge of cold energy rush from his compass into his arm. He didn't pull away this time. He gripped the silver whistle and blew—not a loud blast, but a soft, steady breath.
The water in front of him began to swirl. A small column of water rose from the lake, twisting like a serpent. It followed the movements of Kaito's hand. As he moved his fingers left, the water moved left. When he raised his palm, the water climbed higher, sparkling with the same golden light as his compass.
"I'm... I'm doing it!" Kaito exclaimed, his eyes snapping open. But as soon as his concentration broke, the water splashed back into the lake, soaking him completely.
Oro blinked his ancient eyes. "A good start, but the shadows will not wait for you to practice. The Abyss has noticed the whistle has been blown. They are coming, Kaito. The scavengers of the deep."
As if on cue, the calm water began to boil. Small, red-eyed creatures—deep-sea lurkers—started crawling out from the dark corners of the cave. They weren't as big as the turtle, but there were hundreds of them, and they looked very hungry.
Kaito stepped back, his heart racing. "What do I do now?"
"Apply your lesson," Oro said calmly, sinking slightly into the water. "Defend the altar. If they destroy it, the path to your father's location will be lost forever."
Kaito looked at the small silver whistle and then at the approaching army of monsters. He took a deep breath, his knuckles turning white. The training was over. The real fight was about to begin.