In the late autumn of the fifth year of Keicho, scarcely had the flames of battle at Sekigahara died down when Ieyasu Tokugawa turned his gaze far across the boundless ocean. Amid the rolling waves of the Seto Inland Sea, three enormous Nanban warships cut through the waters, their vermilion lacquered towers glowing blood-red beneath the setting sun. Clad in a jinbaori, Ieyasu leaned against the porthole, gazing east at the faint outline of islands emerging on the horizon — Inazuma, ruled by the Raiden Shogun, and the domain of the Sangonomiya Clan of Watatsumi Island.

 

“My lord, the coastal defenses of Watatsumi Island are weaker than we anticipated.” The iron armor of Tadakatsu Honda clanged with the rocking of the ship. “But according to intelligence from merchants, Sangonomiya Kokomi is currently at war with the Shogunate forces.”

 

Ieyasu stroked the golden ornaments on his tachi hilt, a hidden depth in the wrinkles at his eyes. “When the snipe and the clam struggle, the fisherman reaps the profit.” He turned toward the depths of the cabin, where three Portuguese gunners sat polishing their nautical telescopes. Since the arrival of the black ships, these southern barbarians had brought not only the Bible, but also deadly weapons that reshaped the very form of war.

 

At dawn on the twenty-seventh day of the ninth month, Watatsumi Island still lay shrouded in morning mist. Sayu, a soldier of the Resistance, dozed off in the watchtower with her spear in her arms, only to be jolted awake by an odd noise from the sea. Rubbing her eyes, she looked west and saw three moving castles tearing through the mist, the hollyhock emblems fluttering on their masts like an ominous omen.

 

II. Thunder Shakes the Seas

 

“Load chain shot!” the Portuguese artillery commander roared in broken Japanese. Tadatsuna Mukai, admiral of the Tokugawa navy, swung his war fan. Thirty-six cannons along the ships’ broadsides thundered in unison. The first volley tore off the dome of Watatsumi Island’s palace, sending glazed tiles flying like scattered scales. The shrine maidens praying before Sangonomiya Shrine panicked, only to be swallowed by the second wave of artillery fire.

 

The Resistance camp erupted into flames. Gorou attempted to organize archers to return fire, but shrapnel from shells exploding on the beach rained down like deadly hail. Further along the front lines, Kujou Sara, general of the Shogunate forces, reined in her startled steed and stared in disbelief at the giant spitting fire on the waves.

 

“Foreign troops!”

 

She drew her bow and loosed an arrow, only for it to fall helplessly into the surf a hundred paces away.

 

The Tokugawa arquebusiers had landed on the shoals. Soldiers clad in blue Nanban-style cuirasses formed three ranks, firing volleys in time with taiko drums. Resistance soldiers locked in melee with Shogunate samurai fell in droves, their blood staining the coral reefs of Nazuchi Beach.

 

III. Coral Weeps Blood

 

Sangonomiya Kokomi pushed the power of her Vision to its limit, a watery shield flickering unsteadily amid cannon fire. “Hold fast! Retreat to Mount Ryu!” Her voice sounded faint beneath the explosions. Through the thick gunsmoke, she watched the Tokugawa formation shift — these foreign soldiers did not duel honorably before battle like the Shogunate warriors; they coldly reaped lives with their arquebuses.

 

In the crumbling palace corridors, Kokomi and her personal guard were intercepted by a sudden unit of hatamoto samurai. The young face of Tadayoshi Matsudaira twisted viciously through the smoke. “Take the enemy commander’s head!” In the chaos, Kokomi’s catalyst was shattered by musket fire. She stumbled back against a toppling vermilion pillar.

 

Tadakatsu Honda’s蜻蜓切 — Tonbokiri — sliced through the haze. Kokomi dodged sideways, but could not evade a bullet fired from the shadows. A lead ball from a Nanban flintlock pierced her left shoulder, dyeing her blue-and-white shrine maiden robes deep purple. She knelt upon the broken coral crest, hearing the cries of Watatsumi’s people drifting away on the sea wind.

 

“What a pity.” Ieyasu Tokugawa’s voice came from above, his Nanban-style musket still curling with smoke. “The pearl of Watatsumi Island shall sink beneath the tide of a new era.”

 

IV. Setting Sun Like Blood

 

As the Tokugawa banner rose above the ruins of Sangonomiya Shrine, mop-up operations continued. Kujou Sara retreated with her remaining forces to Kannazuka Island, while Gorou led the surviving Resistance soldiers into Enkanomiya. Takechiyo, the army physician, wrote in his diary: “The waters of Watatsumi ran crimson; floating corpses clogged the waves like rafts…”

 

Ieyasu stood before the captured Sangonomiya sand table, listening to battle reports. The crystallized marrow seized in this campaign would equip three entire units. More importantly, they had gained a stepping stone toward the sea lanes to Liyue. Outside, Portuguese testers fired newly delivered twenty-four-pound cannons, their blasts shaking dust from the beams.

 

“Build batteries. Recruit ronin,” Ieyasu ordered Tadakatsu Honda. “By next spring, the Raiden Shogun’s blade shall not reach our sails.”

 

Twilight fell over Watatsumi Island. On newly erected watchtowers, arquebusiers still shot fishermen attempting to recover their belongings. A sorrowful folk song drifted on the wind, mourning the loss of the Divine Priestess. Far away in Edo Castle, artists began painting new scenes on Nanban folding screens: the hollyhock crest swallowing the three-patterned thunder sigil, heralding the arrival of a new age.

 

V. The Tide Rises Unceasingly

 

On the seventh day of occupation, Tokugawa soldiers captured surviving shrine maidens attempting to flee by sea at Nazuchi Beach. Under harsh torture, they revealed Watatsumi Island’s greatest secret: deep within Enkanomiya lay the remains of the ancient ocean god Orobashi. Upon hearing this, Ieyasu immediately summoned Portuguese craftsmen to plan specially designed diving bells.

 

Meanwhile, the surviving Resistance launched a night raid under Gorou’s command. Using their familiarity with the coral caves, they succeeded in burning half the Tokugawa supplies. Yet against overwhelming firepower, this counterattack was no more than a stone cast into the ocean — stirring small ripples before fading into silence.

 

On the full moon night of the fifteenth day of the tenth month, Ieyasu held a tea ceremony amid the ruins of Sangonomiya Shrine. Alvarez, the Portuguese captain, offered coffee from the New World, its bitter aroma drifting among broken walls.

 

“Next is Liyue,” Ieyasu murmured, tracing the Nanban globe. “Let the Harbor of Stone and Gold also bask beneath the hollyhock.”

 

Countless shooting stars streaked across Watatsumi’s night sky. Old fishermen said these were the weeping souls of the great serpent. Already, Tokugawa warships unfurled sails by newly cast batteries, and blacksmiths clanged through the night forging muskets. On the eastern horizon, thunderstorms gathered — the wrath of the Raiden Shogun would soon descend upon these blood-soaked seas.

 

Epilogue

 

Three months later, within the keep of Edo Castle, Ieyasu Tokugawa watched the Noh play Requiem for Watatsumi. As the scene of Sangonomiya’s fall unfolded, a messenger rushed in with an urgent report: remnants of the Resistance had contacted Liyue merchants and apparently obtained blueprints for the Guizhong Ballista. Ieyasu dismissed the performers. By flickering candlelight, he unfurled a Nanban-drawn map of the Eastern Seas.

 

The sound of waves echoed through time, as if returning to that day of thunderous cannon fire. Beneath the broken foundations of Sangonomiya Shrine, in an undiscovered chamber, a blood letter written by Kokomi before her death glowed faintly in the dark — inscribed upon it was the secret ritual to awaken the ancient ocean god. Beneath the waves, a new storm was brewing.