On June 13th, Marcia and Rodrigo were putting their prototype vessel through its paces.
"This is incredible!"
The prototype was a trimaran. It was the culmination of their efforts to strike the perfect balance between high-speed stability and maneuverability.
While the increased surface area in contact with the water made it slightly less efficient for high speeds than a monohull, the new propulsion system provided by Jin—operating under the name Maquina—more than made up for the deficit.
The output had been doubled compared to previous models of the same type, and it was powerfully driving the prototype through the waves.
"Isn't it amazing, Father?"
"Yeah, absolutely. Jin-dono’s… no, Maquina-dono’s engineering is truly marvelous."
"Arrow, what's our speed?"
"Yes, Marcia-sama. Our current speed is approximately seventy kilometers per hour."
"We cleared our target with room to spare! Do we have anything left in the tank?"
"Yes. The load on the propulsion system is currently at eighty-two percent."
"Good. Alco, let's move on to the maneuverability tests!"
"Understood, Marcia-sama."
The vessel was a five-seater. Alco served as the pilot, while Arrow acted as the engineer. Marcia and Rodrigo were free to focus entirely on monitoring the ship’s performance.
The waters within the bay were calm, making it the ideal environment for such trials.
Alco began with gentle curves, gradually tightening the turns as the test progressed. They maintained a steady speed of around fifty kilometers per hour.
"Hmm. Lateral stability seems solid enough."
Their extensive experience with catamarans was clearly paying off in that regard.
"How is the hull distortion, Father?"
"...Yeah, the girders are creaking just a bit. We should probably add some extra reinforcement there."
With that observation, they decided to wrap up the day's testing.
As they headed back toward Port Rock Town, Marcia let out a satisfied smile.
"Since we have plenty of output to work with, I think we can manage the reinforcements. All that’s left after that is making the seating a bit more comfortable."
＊ ＊ ＊
"Hey, Marcia!"
"Ah, Jin!"
When the prototype pulled up to the workshop, Jin was already there waiting for them.
Marcia and Rodrigo hopped onto the dock, leaving Arrow and Alco to haul the boat back onto land.
"I finished the cushioning material I promised, so I brought it over."
The material in question was Expanded Magi-Polyethylene, a substance developed by Saki and known simply as EMPE.
"Let me see... Wow, this is so light!"
"Right? It doesn't absorb water, so if you pack it into the ship's voids, it'll double as a buoyancy aid to prevent flooding."
"Oh, that’s a great idea."
"I see you’ve finished the prototype."
Marcia nodded happily at Jin's observation.
"Yeah. There are still a few things to tweak, though. Jin, would you mind taking a look?"
"Of course, I’d be—"
He was interrupted by a frantic cry.
"Death Sea Serpents! They've appeared!"
A desperate shout echoed from a ship that had just come racing back into the harbor.
"What?"
A security guard hurried over to get the details from the man. Jin, Marcia, and the others followed close behind, listening intently.
According to the report, two Death Sea Serpents had surfaced north of Toryu Island, which lay just past Io Island.
Three boats had been fishing in the area. One had been capsized, though the crew had been lucky enough to be pulled from the water by a nearby vessel.
However, that second boat had then been pursued by the monsters. The crew had barely managed to beach the craft on Toryu Island and flee inland, but the vessel itself had been smashed to pieces.
The boat that brought the news had been the furthest away from the monsters. Since the Death Sea Serpents had focused their aggression on the other two vessels, they had managed to escape with their lives and reach Port Rock Town.
That they had been aboard a high-speed vessel from the Marcia Workshop had undoubtedly been their saving grace.
"We should dispatch a rescue mission to Toryu Island via hot air balloon. Just to be sure, there are five people stranded there, correct?"
"Y-Yes, sir."
"Then we can handle the rescue if we send two units."
Unable to remain a mere observer, Jin spoke up.
"If we take Konron 3, we can reach them in no time."
Jin had arrived in Port Rock Town aboard Konron 3 that very day. He had an invitation to meet with Marchioness Firenziano in Florenz later, and since he couldn't very well use the Taube for a casual visit, he had opted for the airship.
It was already 4:00 PM. If they began preparations for the hot air balloons now, the sun would likely be down before they even reached the island.
"Konron 3?...Wait, are you the Lord of Kunlun!?"
"Yes, I am."
"M-My apologies for the lack of protocol! I am Dorusen Battle, Captain of the Port Rock Coastal Security Guard. Sir, may we count on your assistance?"
"Certainly."
Dorusen appeared to be an earnest man in his late twenties.
Jin sent a mental command via manacam to Reiko, instructing her to tell Edgar to bring Konron 3 around. He designated the Central Plaza as the pickup point.
"Father, he is on his way," Reiko reported.
"Good."
Jin relayed the information to Captain Dorusen, and they hurried toward the Central Plaza.
Jin, Reiko, Dorusen, a few other guards, and Marcia arrived at the plaza almost exactly as Konron 3 made its descent.
"It's dangerous, everyone stay back!"
The security guards cleared a space among the tourists and curious onlookers, allowing Konron 3 to land without incident.
"Right, let's go."
"Jin, I want to go too," Marcia said. "I need to see a Death Sea Serpent with my own eyes if I’m going to build ships to fight them."
Jin agreed, and Marcia climbed aboard.
With Jin, Reiko, Marcia, and Dorusen on board, Konron 3 soared into the sky.
"Incredible! This is... amazing!"
Dorusen was wide-eyed with shock; it was his first time aboard an airship.
"Marcia, Toryu Island is that way, right?"
Jin pointed in the direction opposite the setting sun.
"Yeah. From Port Rock Town, Toryu Island is further east, past Io Island."
"Edgar, take us in."
"Understood, Jin-sama."
Konron 3 cruised through the air at a hundred kilometers per hour.
"So fast!"
Dorusen continued to marvel at the speed, but Jin and Marcia were focused on the horizon. Below them, they could see the two Death Sea Serpents closing in on Port Rock Town.
"Are those them? They're... massive."
One was roughly thirty meters long, a specimen that ranked among the largest of its kind.
"This is bad! If they keep going, they'll reach the harbor!" Dorusen shouted, his face pale with fear.
"We have to deal with them before we can worry about the rescue, or things are going to get ugly."
As Konron 3 was the only vessel capable of intervening, and since he was already here, Jin decided to take care of the monsters.
"Edgar, get us directly above them."
"Understood."
Konron 3, which had been racing east, performed a smooth 180-degree turn. Slowing to thirty kilometers per hour, it held its position directly above the serpents.