Yuki followed Anna and Wanda through the hallways to his assigned workshop, a massive space filled with tools, holographic displays, and prototype parts.
"Welcome to your playground," Anna said, gesturing around. "Everything you need is here. And yes, you can modify anything you want."
Yuki's eyes scanned the room, lingering on the advanced machinery and hovering fabrication units. He took a deep breath. "Alright… first step, analyze the conditions we'll face down there."
Wanda floated a hologram in front of him. "Temperature, pressure, density of the water, magnetic interference… all of it's been compiled. I also included data from the energy signal."
Yuki studied the display, his fingers moving rapidly across a console. His aura shimmered faintly as he overlaid multiple calculations and simulations. "If the submarine isn't reinforced for these conditions, it'll collapse before reaching the bottom. Hull density, adaptive pressure fields, magnetic shielding… we'll need to combine them all."
Anna leaned against the worktable, watching quietly. "Remember, this isn't just an engineering test. You're leading a team."
Yuki nodded, already visualizing the submarine. Using the artifact cores Anna had given him earlier, he began sketching adaptive components that could morph in response to external pressure and magnetic fields. "We'll need propulsion that can maneuver in extremely dense currents and maintain stability even under sudden energy fluctuations."
Wanda whistled. "That's… impressive. Even if the theory was right, seeing it in action is something else."
Anna smirked. "I trust you know what you're doing. Just… don't blow up the workshop this time."
Yuki laughed lightly. "No promises."
Hours passed as he fine-tuned every system: magnetic shielding, pressure adaptation, sonar arrays, and energy absorption fields. Finally, he stepped back and activated the cockpit interface. A holographic checklist appeared, confirming operational status.
"Hull integrity… 99.7%," he muttered. "Propulsion calibrated. Pressure adaptation optimized. Energy shields synced."
Wanda raised an eyebrow. "You're sure about that last one?"
Yuki nodded. "If anything interferes with it, I'll know immediately. The shields will adapt in real time."
Anna smiled. "Good. Let's start to build it."
And so, between complicated testing and building the whole thing, two months passed, and finally, today they were to conduct the test dive.
Within minutes, the exploration team assembled: Wanda at his side as sub-captain, Ruri monitoring external communications, and two other elite operators specialized in underwater reconnaissance. Yuki quickly briefed them, overlaying the holographic ocean map and energy signal path.
"Conditions below the trench are extreme: pressure, currents, thermal vents, and unknown energy fluctuations. Our objective is to test run this little sub we now call 'Mama Hein' in the environment it was created for."
All nodded.
"Understood," Wanda confirmed.
Anna patted his shoulder. "Remember, be careful."
Yuki smirked. "Careful is boring. Let's dive."
Yuki climbed into the main cockpit, his fingers hovering over the controls. Wanda secured herself beside him. "All systems checked?" she asked.
"Hull adaptation is online," Yuki replied. "Pressure shields active, energy modulation synced. Small sub, drones, and monitors are ready for deployment at any point."
Ruri monitored the external sensors. [Thermic Fog in this zone is extreme. Temperature drops rapidly below this depth, and magnetic interference is high. I recommend staying in adaptive mode for the entire descent.]
Anna's voice came through the comm. [Remember, your priority is survival and observation. Don't push the sub beyond limits.]
Yuki smirked, activating the main thrusters. The hull rippled as adaptive plating shifted in response to the rising pressure. The water outside the bay churned, currents twisting unpredictably, but the submarine held firm.
"Engage descent," Yuki commanded.
The sub sank slowly, the smaller craft remaining docked and ready. Sensors tracked pressure, water density, and magnetic fluctuations, feeding real-time adjustments to the adaptive hull. Every layer of Thermic Fog thickened as they reached deeper depths, but the main sub maintained stability, energy shields compensating for the sudden drop in temperature and extreme currents.
Wanda observed the displays. "Hull integrity holding at 93%. Energy shield fluctuations within safe limits. All the sub systems are ready for deployment."
Yuki nodded. "Good. We'll use them when we need to scout the trench directly. The main sub stays stable away."
Ruri's voice interjected. [The energy signal is on a safe descent. We approach the end of the fog.]
Yuki nodded. "Alright… stay alert. We'll descend carefully from here, keep the main sub stable, and deploy the smaller craft to navigate deeper if necessary."
The submarine continued its silent plunge, currents buffeting the adaptive hull. The Thermic Fog thickened, the pressure rising exponentially, but the main sub adjusted instantly, keeping all members safe. As the crew leaned forward, eyes on the displays, the faint energy signal pulsed ahead, guiding them deeper into the unknown, a hidden world beneath the sea, waiting to be uncovered.
As the fog dissipated slowly, they found themselves in the open deep sea again.
[All the readings are clear. We passed through safely. Deploying the scout drones. Sonar resonance picture is live in... 3... 2... 1.] Ruri's voice came from the speakers, and soon a grey picture appeared, detailed but colorless.
The approach Yuki took in his submarine was not lighting their path but using sonar perception to build a picture, mainly to avoid disturbing the environment and lower the risk.
Of course, that's just for the start.
[All readings are green. No high percentage of risk detected. The unknown signal is in a safe distance. Lights live in 5 seconds.]
Soon the view around lit up, leaving the group shocked. Most of those inside were quite intellectual and had great faith in their experience.
And now they could recognize some of the creatures around; hell, most were from the Jurassic era.
Sadly, their surprise was cut short by an alarm.
[Sir, I detected a rescue signal. It's from the research institute on the other side of the trench,] Ruri's voice came, alarmed.
"But why now?" Yuki asked.
[Likely thanks to magnetic interference in the fog. Also, thanks to the scout drone, I discovered something.]
The main screen changed to show a wall deep underground, but it was formed by the same Thermic Fog, and it appeared to be coming from the seabed, forming walls, then joining the hiding mist horizontally.
"I see, so this is where it comes from," Yuki commented, then changed the screen to the view of the drones. What he saw confirmed his theory: every drone who passed a wall found itself in a completely different geography. The same deep sea, but a different kind of creature and plant.
"Amazing. Like a natural zoo, but with sections for each historical period stuffed together."
Then it hit Yuki. Looking back at Wanda, he commanded, "Blow the tanks now!"
Wanda looked at him, confused, but Yuki didn't answer. "Just do it."
Trusting his call, they blew their tank and started to ascend immediately.
"It's the same kind of substance, so why can that creature pass through it vertically but not horizontally?"
Wanda looked at him in confusion, then her eyes widened. "Right, unless it chooses not to."
"Exactly, and the movement we took as if he was in prison, it wasn't; it was just him strolling around his territory," Yuki said.
"But why blow your tanks?" Wanda asked, still confused.
But Yuki gave her an "are you serious" face. But the one who answered was a scientist from the crew.
"If it chooses not to leave, then it's a territorial creature. Add that with the way the creatures are organized. I will take my chance and say that it wasn't natural," the scientist took his eyes off the screen, "and that's probably what's causing the signal."
This let Wanda feel a cold sweat all over her body. Then she remembered, "The distress call? Now we know what caused it."
"No, he means the arrangement of the whole undersea environment," Yuki rebuked.
"Eh, does that mean he can control this weird cloud? Then we are in danger?"
"That's why I blew our tank," Yuki said. "The moment we get out of the Thermic Fog, we will speed in their direction and dive below it again, better than speeding through unknown territory."
Yuki tapped something, and a data screen appeared about the Thermic Fog.
"I sent them a message, and along with it, I took their status of the Thermic Fog," Yuki said, pointing at something.
"The place we just dove has a deeper penetration, while over there it is much thinner. And taking what we found below, I bet this zone is older than where they are now."
"Sadly, we already blew our tank; we have to surface before we could dive again," Wanda said with a deep sigh, about to ask Ruri to calculate the time needed.
"That's why the small sub is for," Yuki said and looked at her. "The moment we leave the fog, you and I will take the small one; it can hold six people. We could use the rest of the hold to save them."
"Okay, then, but I am driving," Wanda said.
"Ha, not a chance, my craft, my driving seat." Yuki snorted.