# Chapter 551: Sound Wave Storm
Below, dozens of Crimson Fish Beasts let out cries that rose and fell in succession. They spread their pair of blazing wings, pierced through the seawater, and flew upward, forming an encirclement as they charged toward Zhang Ruochen and the others.
Every single Crimson Fish Beast was an extremely ferocious creature, let alone dozens of them attacking at once.
"So that's how it is. The Crimson Fish Beasts entered the Western Mysterious Sea from here."
Zhang Ruochen finally understood what was happening, feeling a sense of sudden realization.
Crimson Fish Beasts lived year-round in the magma deep within the earth's core. Without special circumstances, it was almost impossible for them to reach the surface.
The Blood Spring Sea Trench was tens of thousands of zhang deep, reaching straight down to the earth's depths, connected to the magma layer. The Crimson Fish Beasts could thus pass through the Blood Spring Sea Trench, burst out of the magma layer, and enter the Western Mysterious Sea.
At the same time, Zhang Ruochen thought of another matter. The average depth of the Western Mysterious Sea was less than two thousand meters, so why was the Blood Spring Sea Trench tens of thousands of meters deep?
Zhang Ruochen suspected that the formation of the Blood Spring Sea Trench was caused by human force.
Perhaps it was that iron pillar, falling from the sky, piercing through the Black Tortoise's body, driving the Black Tortoise deep into the seabed, while also creating this tens of thousands of meters deep trench.
One could imagine how powerful a force it must have been to create a pit tens of thousands of meters deep.
"Croak!"
A Crimson Fish Beast at the fifth transformation of Fish-Dragon realm flew above Zhang Ruochen, swung its tail, and lashed toward Zhang Ruochen's neck.
"Shua!" With a sound, Zhang Ruochen drew his Abyssal Ancient Sword, dragging a long streak of sword light. He slashed forward, cutting off a section of the Crimson Fish Beast's tail.
That Crimson Fish Beast cried out in pain, becoming extremely furious. It quickly swung its claws, piercing through Zhang Ruochen's protective energy barrier and striking his chest.
Zhang Ruochen crossed the Abyssal Ancient Sword in front of his chest. Dozens of sword qi flew out from the sword body, forming a layer of sword curtain that blocked the Crimson Fish Beast's claw strike.
Having lived year-round deep in the earth's core, Crimson Fish Beasts had long adapted to such an environment. Thus, the water pressure of the sea had a relatively weaker effect on them.
Therefore, the power unleashed by this claw strike was exceptionally strong, even knocking Zhang Ruochen backward.
"Swish!"
Zhang Ruochen immediately turned around and rushed into the Black Tortoise's left eye.
Standing at the edge of the eye socket bone, like standing at a cave entrance on a cliff wall, he gripped his sword with both hands and slashed forward, unleashing a waterfall of sword qi that drove back that fifth-transformation Crimson Fish Beast.
"Boom rumble!"
Above the Black Tortoise's back, the Ground-Standing Monk and the Black Bone Flood Dragon King joined forces, battling the Earthfire Qilin.
To survive, they had to cooperate; otherwise, the Earthfire Qilin's powerful strength would tear both the man and the flood dragon apart.
Zhang Ruochen knew well that the Ground-Standing Monk and the Black Bone Flood Dragon King couldn't hold out for long. With the Earthfire Qilin's strength, it would soon defeat them.
Thus, Zhang Ruochen immediately gave orders: "Xiao Hei, you stay here with me to resist the Crimson Fish Beasts' attacks. The rest of you, immediately go deep into the Azure Flame Black Tortoise's body and try to seize its inheritance as quickly as possible."
The Azure Flame Black Tortoise's eye socket was a very narrow entrance. Defending here could achieve the effect of "one man holding the pass, ten thousand unable to break through."
With him and Xiao Hei defending, keeping the Crimson Fish Beasts outside, Huang Yanchen, Ao Xinyan, and Orange Moon Star Envoy could go seize the Black Tortoise's inheritance, which would be relatively much safer.
Zhang Ruochen immediately took out a Wish-Fulfilling Treasure Bottle, held it in his palm, and began urgently collecting the Black Tortoise qi flowing out from inside the Black Tortoise's body.
Zhang Ruochen's main purpose in coming to the Blood Spring Sea Trench was to collect Black Tortoise qi and Black Tortoise sacred blood. As for the Black Tortoise's inheritance, he wasn't very interested.
After all, he cultivated the "Nine Heavens Bright Emperor Scripture," which was itself an extremely high-level cultivation technique. There was no need to switch to the incomplete "Black Tortoise Sacred Canon."
Moreover, he also possessed the Dragon Pearl and the Sarira, meaning he simultaneously had the inheritances of the Golden Dragon and the Buddha Emperor.
Neither the Golden Dragon nor the Buddha Emperor was any weaker than the Azure Flame Black Tortoise.
Since he already had their inheritances, the Azure Flame Black Tortoise's inheritance could be taken by Huang Yanchen, Ao Xinyan, and Orange Moon Star Envoy. Let's see who had the better luck.
Xiao Hei looked at Huang Yanchen, Orange Moon Star Envoy, and Ao Xinyan, saying: "The most important treasure on the Azure Flame Black Tortoise is its Sacred Source."
"The Sacred Source not only contains the Azure Flame Black Tortoise's lifelong sacred power and spirit but also its knowledge. Whoever can swallow the Black Tortoise Sacred Source can be considered the true inheritor of the Azure Flame Black Tortoise."
The Azure Flame Black Tortoise had many treasures, but none could compare to the Black Tortoise Sacred Source.
Since no Black Tortoise Sacred Source was found on Huang Shenyi's body, it showed that with Huang Shenyi's cultivation at the time, he couldn't take the Sacred Source. That meant the Sacred Source must still be inside the Azure Flame Black Tortoise's body.
Zhang Ruochen suddenly thought of something and gave another instruction, speaking solemnly: "When you enter the Black Tortoise's body, you must be careful. If the Golden Huang King has already taken the Black Tortoise Sacred Source, don't compete with him."
The Golden Huang King had arrived at the Blood Spring Sea Trench long ago, but everyone hadn't seen him yet.
Therefore, Zhang Ruochen strongly suspected that the Golden Huang King was likely inside the Black Tortoise's body, collecting its inheritance.
Perhaps it was because of the Golden Huang King's disturbance that those Crimson Fish Beasts and the Earthfire Qilin had burst out of the underground magma and entered the Western Mysterious Sea's surface.
The Black Tortoise's inheritance wasn't very attractive to Zhang Ruochen.
But for other cultivators, even for Half-Saints, it was a fatal temptation.
The Golden Huang King would also care greatly about the Black Tortoise inheritance. He was a Half-Saint-level existence. If he had already found the Black Tortoise Sacred Source, Huang Yanchen, Ao Xinyan, and Orange Moon Star Envoy competing with him would be like moths flying into a flame.
So Zhang Ruochen gave this advance instruction to prevent them from causing unnecessary trouble.
Huang Yanchen, Ao Xinyan, and Orange Moon Star Envoy immediately used their movement techniques, passing through the bone tunnel in the Azure Flame Black Tortoise's eye, heading deeper inside.
But they had only reached the Black Tortoise's throat when something went wrong.
The Black Tortoise's body shook violently.
The next moment, a world-shaking roar came from the Black Tortoise's abdomen.
"Hoo!"
The roar was extremely high-pitched, forming a sound wave storm.
"Damn it! Someone is in the Black Tortoise's abdomen. He's stopping us from entering. Retreat!"
They wanted to retreat, but it was too late.
"Boom rumble!"
The sound wave storm came rushing toward them.
Huang Yanchen immediately infused her true qi into the Mysterious Turtle Shell. Light radiated from the shell, forming an energy shield that protected the three of them inside.
"Bang!"
The defense formed by the Mysterious Turtle Shell was like a sheet of paper, instantly shattered by the sound waves.
The other party wasn't trying to stop them from entering the Black Tortoise's abdomen—he wanted to kill them.
The sound wave storm struck the three of them. Even with their cultivation, their eardrums were shattered by the sound waves. Blood flowed from their seven orifices, their bodies flew backward, and everything spun around them.
Then they felt as if they had crashed into a hard bone wall. Their brains were struck with a loud bang, their vision went black, and they fainted, collapsing limply to the ground.
"Not good."
The moment the roar sounded, Zhang Ruochen's body was pushed back a step.
But his reaction speed was extremely fast. He immediately fully activated his true qi, stomped his feet downward with force. With a "chi" sound, his legs sank half a foot deep into the Azure Flame Black Tortoise's body like two nails.
That wave of sound storm continued to surge out from the Black Tortoise's abdomen, striking Zhang Ruochen.
"Space Distortion."
Zhang Ruochen controlled his Space Domain, slowly moving his hands, mobilizing space power, causing the surrounding space to undergo subtle distortion, allowing that violent sound wave power to slide past his side.
The Black Tortoise's eye socket became like a loudspeaker. The sound wave storm continuously surged outward, turning into rings of powerful sound wave force.
The dozens of Crimson Fish Beasts that had rushed to the Black Tortoise's eye socket were all blasted away by that sound wave storm, crashing into the distant stone walls, smashing out a large area of pits.
"What happened?"
After the sound wave storm passed, Zhang Ruochen's expression changed drastically. He was extremely worried, afraid that Huang Yanchen had met with misfortune. So he immediately rushed into the Black Tortoise's body to find her.
In a corner of bone, Zhang Ruochen found the unconscious Huang Yanchen. Her eyes, mouth, ears, and nose were all covered in blood. Even the skull at the back of her head had a cracked gap, with blood continuously flowing out.
Zhang Ruochen immediately extended two fingers and pressed them on Huang Yanchen's wrist to check her injuries.