The Throne of the Deep Frontier | Jan Teschner

Underwater City Lematoa – After cutting the lines on the magical spying network in Tripoint and neutralizing the King’s stationed forces, the party set their sights north. The mission was clear: intercept the Nalua king before his long-planned invasion could hit the surface. With currents far too heavy for the Flux Engine to handle alone, the ship’s unpaid deckhands returned to the oars, grumbling like they were working a double shift without any overtime.
Days later, the water cleared with unmistakable grit. Coral spires and underwater mountain ranges stretched beneath them like a second, uncharted continent. It was undeniable now: they were sailing right over a massive, hidden stronghold.

An Unfriendly Border Encounter
Fearing the anchor might snag or snap in the reefs below, the party ordered Marina to hold position while they descended to scout the territory. Merlin, T。yana, and Ainz downed the last of their water-breathing algae and dove overboard. Though clearly not in fighting shape after their previous celebrations, Selah and Mad Matt insisted on joining - if only to keep an eye on the perimeter from the rear.
The city streets were a ghost town. Coral archways and smooth stone roads suggested ancient craftsmanship, but the locals had gone into hiding. From behind thick, colored-glass windows, suspicious eyes watched their every move. It was obvious: the citizens had been warned of these uninvited intruders.

Negotiating a Peace Treaty (Sort Of)
Never one to pass up an opportunity for some frontier diplomacy, Merlin approached a nearby home. His knock triggered a wave of pure panic behind the door. After a tense standoff, a terrified resident cracked it open. Undeterred, Merlin offered five gold coins in exchange for supplies. Language barriers made things messy, but a bit of hand gestures and some candy seemed to settle the deal. He gestured “fish” and handed over some Haribó. The host - still wary of this lawless group - offered him a bowl of bubbling fish stew, brewed on a small underwater stove. Merlin briefly questioned the physics of underwater cooking before happily devouring it, offering a polite nod before heading back to the squad.

Scouting the Stronghold
The royal palace dominated the skyline, a cathedral-sized fortress crowned with shells and towers. Its gates were wide open, yet there wasn't a single guard in sight. Inside, coral mosaics lined the halls. Tiyana scanned for any magical signatures of an ambush, but Ainz stepped forward with total confidence, analyzing footprints and magical traces with tactical precision. He noted that the left staircase had seen 9ines usage recently, while the right saw 96. To maintain a balance of energy, he and Tiyana ascended the left stairs, while Merlin, impatient to get to the action, vaulted directly to the upper landing.
At the door, a large circular rune was carved into the ground - the counterpart to the communication device they had dismantled in Tripoint. Ainz recognized the design immediately: an advanced scrying circle, likely used to coordinate with the southern observation post. Tempted to disrupt or hijack the signal, the group ultimately chose restraint. Instead, they turned to the door, which yielded easily to a single push from Merlin.

The Sovereign’s Grievance
The final chamber was vast and silent. Fish glided between floating lanterns, and at the far end, a throne sat atop a coral platform. There stood King Valili, tall and commanding, with azure skin and a long trident whose center prong looked like a heavy lance. His voice, though calm, carried the weight of centuries of conflict.
He accused the party of disrupting settlements in Manamea and Camborne’s Rest, eliminating his scientists, and leaving no survivors in Tripoint. He recounted the Great War from 500 years past, when the expansionism of the surface world forced the Nalua into the deep. There, they had secured the Flux Crystals to sustain their lives - but not their peace. Valili had long been preparing his counter-strike.
Before he could launch his assault, Ainz attempted to charm the king. Valili sensed the magical interference, snarified in fury, and hurled his trident with lethal intent. The skirmish had begun.

Full-Scale Engagement in the Deep
The trident slammed into the ground, but the adventurers dodged the impact. Valili summoned the power of the Flux, slowing the flow of time around the room to a crawl. Every movement from the party became sluggish and labored. Merlin charged forward to close the distance but was quickly caught by the king’s weapon. Tiyana, refusing to back down, unleashed a barrage of magical artillery from afar.
Ainz summoned a spectral dragon made of acidic water - its form unstable in the currents. The team dubbed it Draco Malformed. It slithered through the water toward the throne like a tactical strike force.
Merlin danced around Valili to stay clear of Draco’s path, but Valili mocked him for abandoning his comrades. He leapt off the platform toward Tiyana, braving a storm of conjured icicles. She narrowly dodged and utilized an Invisibility spell, repositioning herself to launch spells from cover.
Angered by the king’s taunts, Merlin leaped down after him but failed to land a decisive blow. Valili summoned a pressurized pillar of water that nearly crushed Merlin into the coral below. Gritting his teeth, Merlin stood his ground through the pain.
Ainz directed Draco Malformed to attack, sending acidic claws and poisonous breath toward the king. Merlin stabbed Valili’s shoulder twice, drawing blood and staggering him. From the shadows, Tiyana delivered the final volley of Magic Missiles. Valili collapsed.
In his dying breath, he begged the adventurers to spare his people - ordinary Nalua citizens who had no part in his crusade.

The Star Devourer Revealed
Before the party could respond, a dark flash erupted from the throne room entrance. Nalzagoth, the Star Devated, tore free from Mad Matt’s body. Matt, left hollow and reeling, collapsed as the entity floated into the chamber. The entity mocked Matt’s weakness - noting he had failed to participate in the fight - then turned to Valili, praising his ambition. Without hesitation, Nalzagoth invaded Valili’s wounded body.
A storm of black stars consumed the throne. Merlin, still holding the king, felt a surge of pain through his arms. With great effort, he hurled the king away. Valili's body didn’t fall into the depths below; instead, it rose above their heads.
Out of the blackness emerged a titanic new form: Valili reborn as a Great Water Dragon, with glowing eyes and coiling waves swirling around him like a storm.

The coral beneath their feet began to crack.