Anyone who often survived in the wilderness knew this: eating wood was easy; passing it was hard.
That was because humans lacked the symbiotic bacteria needed to digest lignocellulose.
Shipworms had them.
Their digestion depended entirely on those symbiotic bacteria.
With that, Veylin's approach became clear.
Attacking the shipworms themselves meant battering against an impregnable wall.
But what if that sturdy fortress depended on a band of fragile supply troops to function?
He rose and found Master Valerius sorting through documents in another room.
"Master, I have an idea, and I need your wisdom."
The old alchemist walked over to Veylin and studied the image under the microscope, puzzlement in his eyes.
"Sir, forgive my frankness, but your approach has gone completely beyond the bounds of traditional biological toxicology."
"Master, what I want to destroy is these symbiotic bacteria. They're fragile, but they hide inside the shipworms' digestive tracts."
"So I need a substance that can suppress their activity. It should have thick root bark with plenty of fibers, and feel like cotton fluff when torn apart. It should keep for a long time after drying, and when boiled in water, taste bitter at first, then sweet."
Valerius stroked his graying beard and sank into thought.
"Your description reminds me of ghostface mulberry. The mountain natives boil its root bark in water and pour it into streams. The fish become paralyzed and float to the surface. But how do we get the agent inside?"
"That requires a second ingredient," Veylin continued. "A powerful penetration aid. It needs to break down the fatty layer on an organism's surface and open a passage for the agent. Substances like that usually come from some extremely bitter seed."
"Then oil pressed from stone bitterfruit is exactly what you need!" The master's eyes lit up. "Its mild corrosiveness is just right! But we still face the same problem: how do we keep these two substances firmly attached to a hull in seawater, rather than letting the water dilute them?"
Veylin sank into thought as well. That was indeed a bottleneck in his plan.
Suddenly, the master slapped his thigh. "I remember! Years ago, I sailed to the Mist Isles. The natives there have a ceremonial 'gel' made by boiling a seaweed called siren's hair. It doesn't disperse in water, and it has an extremely strong affinity for wood! They use it to preserve their ceremonial boats! It's cheap, and there's plenty of it!"
The old man looked at Veylin with admiration. "Genius! An absolutely brilliant idea! Combining three materials whose magical properties have nothing in common, perfectly, through an entirely new theory! This isn't alchemy anymore. This is... the Creator's logic!"
Veylin neither agreed nor disagreed. "I'm merely turning theory into a practical 'weapon.'"
Back in the present.
After listening to Veylin's account, Caroline stared blankly at the glass jar on the desk. The corpses of several "calamities" inside were grotesquely swollen.
A few seconds later, her shoulders began to tremble slightly.
Not from excitement, but because the pressure that had kept her from drawing a full breath had finally, in that instant, come crashing off her shoulders.
She did not cry. She merely sank slowly back into her chair and covered her face with her hands, a muffled sound somewhere between a sob and a laugh escaping her throat.
It took a long while for her to catch her breath. When she raised her head, the exhaustion and vulnerability in her green eyes had been replaced by a rekindled flame.
"Wonderful!" She sprang to her feet. "I'll get people together right away and put this..."
Veylin supplied, "β-1,4-glucanase inhibitor."
Caroline froze for a moment at that. "Um... inhibitor into the harbor! We can save the remaining ships!"
She eagerly reached for the glass jar on the desk, ready to rush out and summon her subordinates, who had already lost all hope.
Without a change in expression, Veylin drew the jar containing the "antidote" a little closer to himself. It was a tiny movement, but his stance was unmistakable.
Caroline's outstretched hand stopped in midair. She paused, then frowned. "What do you mean by that?"
Veylin rested his hand lightly over the jar and looked at her calmly. "Now, everything concerning you and the Golden Sail Merchant Guild concerns me." He continued as though stating a simple fact. "And when I deal with a problem, I like to maximize the gains."
The abrupt, strangely possessive remark sent Caroline's thoughts in an unwelcome direction. The tips of her ears reddened, and she was about to set him straight.
"You..."
"I don't know how to run a business."
Veylin cut her off, his gaze seeming to pierce the walls and reach the chaotic harbor in the distance.
"I was merely thinking, Lady Caroline. A perfect plague requires three things: a deadly pathogen, widespread means of transmission, and... the only cure."
He paused and looked into Caroline's eyes. Only when that flame flared brighter did he continue. "Our enemies gave us the first two, and now we have the third. Do you think the cure's only purpose is to heal the disease?"
That single sentence exploded like a thunderclap in Caroline's mind.
Her brilliant merchant's mind, brought to a temporary standstill by despair, sprang back to life and began working faster than ever before.
The cure... an information gap...
The enemy's stranglehold... the monopolized raw-material market... the technical team they poached...
Countless fragments of information collided and rearranged themselves in her mind. A wildly, breathtakingly audacious plan rapidly took shape.
Her lips moved as she silently mouthed a few words.
Smokescreen... concealment... trap...
Her eyes grew brighter and brighter, gleaming with a mixture of excitement and cruelty, like a lioness that had finally caught the scent of prey.
This was no longer a simple counterattack.
She was going to drag those self-important vultures into the trap, skin, bones, and all!
"Ha!"
Caroline gave a short laugh, then punched Veylin in the shoulder so hard that he stumbled half a step back.
She leaned closer, her eyes astonishingly bright in the dim light, roiling with cruelty, excitement, and admiration.
"You devil... no." Her voice dropped low. "You're much cuter than the devil."
With that, she turned away as though her earlier loss of composure had never happened.
The instant she turned, she became the Silver-Haired Witch once more, clad again in iron resolve and authority, sharper and colder than ever.
She yanked open the office door.
"Freeman! Gather every department head! Immediately! Right now!"
Her commanding, decisive roar echoed through the corridor outside.
Veylin stood where he was, watching her brisk figure disappear at the end of the corridor. He knew that this revenge, for which he had personally placed the blade in her hand, had only truly begun at this moment.
He added softly, as though speaking to the air, or reminding himself, "The show has begun."