Battle was below.The unmistakable sound of distant defense claxons echoed up, painting a confusing scene. Distorted shapes and angles pelted their mind, but they sensed what they were diving into.

Outline of a city.

Hard edges of buildings.

Bunkers being lit up with directed sounds.

Lines from the swimlanes.

They caught the fresh scent of old blood. A coppery welcome for the accidental refugees.

Four bunkers formed a small line of defense on the edge of the city. All around were broken things. The noise produced spotty and incomplete images. Some buildings appeared to be toppled and crushed, but they all dared to hope it was poor echoes or rooftop silt fogging the image.

There was an intense warble that had them sensing deafness as if caught in the line of directed sound. The defenders had soundmakers and were occasionally sweeping above them, but mostly concentrated on lighting up the offensive lines.

Thermal-Rock was the first to speak. “Where are we?”

“We must have drifted from Deepvent, this is Littleseep.” Sand-Stirrer said. “I used to live over by the town square.” Littleseep was a suburb that was built around a marginal warm-water outflow. Still, the town thrived from the heated water and being on a trade route with Deepvent. It also had good defensive features. Mounds of naturally formed lava domes hollowed out and reinforced and small ground out defensive windows that allowed the defender to stab a spear in any direction, but made it difficult for the attacker to get the same angle.

“Hold up!” Ice-Driller commanded, and the descent slackened.

“The soldier’s quarter is close to the square.” Sand-Stirrer said and re-flashed the rough grainy sound-image he had pictured on the way down.

Ice-Driller immediately tried to force their descent toward the ruined building that Sand-Stirrer identified. The scene was as chaotic as imagined from above. The confusing echoes they first pictured were accurate. All around refuse, rocks, weaponry, and the dead were strewn. Some buildings were untouched, while next to it another had a glancing strike from a siege rocks and one corner of the top floor was crumpled. A third building had multiple hits and looked in danger of being pushed by the next strong tide.

They landed in the open plaza.

The Overworld Stone went as it hit a large broken shell that was loose on the ground. They all dragged the stone and the net under the nearest overhang.

Above them, the Object stopped and held position.

“What now?” Study-Up asked. They were now shielded from the deafening roar of the battle lines.

“I need to find the officer in charge. We need to get it to Deepvent.” Ice-Driller said.

“The soldier’s Quarter is one row there, left another, then down a level.” Sand-Stirrer said as he sent a mental image. Then he cast a ping down an alley. Its echo returned a littered image.

“What should we do with the object?” Thermal-Rock asked as he shot a ping up at it. The object was frequently sending out more pings to distinguish objects in the confusion. The answer seemed obvious, but it was the kind of answer that only returns if asked.

“Take it where it wants to go.” Ice-Driller replied. “You two, lead the Otherworld Object towards the plaza and see if it will park over the warm vent. Study-up and I will see if we can even get to Deepvent in this chaos.”

Ice-Driller and Study-Up swam away. “And be careful! Beware the darts. Ping above before darting across the street.” Sand-Stirrer implored them. The ‘beware the darts’ was an image of them being impaled by spikes.

“I’m not some paralarvae. I know how to protect my melon from above.” Ice-Driller replied. The two headed off towards the city center. They ducked under overhands and beneath walls toppled over the streets..

The smell of blood was in the water and the wailing of the scared huddled in basement floors echoed off every hard, flat surface. The cries were so clear the two could picture their shit-scared expressions that echoed around corners and through walls.

Ice-Driller and Study-up stopped at the intersection as the alley emerged to another street. The sign above was for a food market called Whitebait and Roe.

Across the road, another sign hung loosely from its post. Shells and More. The exterior of the building was intact, but jets of detritus surrounded it. It lacked any more horizontal flooring as a heavy boulder hit it dead-center. It was all one vertical swimpath. The contents of the floors: doors, shells, furniture, etc. burst out from every opening because of the collapsing roof, forcing overpressure water and carrying out any item the current could carry.

Ice-Driller looked down at the swimlane and then pinged up to check for darts. “Quick,” he said, and they darted to the next street. He looked back and saw someone trying to gather up knickknacks from the street. A looter perhaps, or a ruined shopkeeper in despair. All around him, the wails of panic or mourning cried out, while the scent of fear wafted through the water. “Get out of the road,” he called to the decapod, but they mindlessly filled up their hands with worthless items.

Ice-Driller pressed ahead with Study-Up and they looked down onto a plaza filled with makeshift barricades angled to protect their top flank and pointed towards the enemy. Down and to the front of the plaza was a bunker.

The sounds of orders being yelled rang out from below: “Get down, you larvae.” / “Watch your melons.” / “Counter if they swarm the bunker.”

Occasionally, pings went up and out to return echoes for them all to visualize. Ice-Driller and Study-Up could see the militia below interspersed with the army. The militia was formed of any citizen with a pointed metal tool or fitted shell for armor. No two militia members had the same look. Meanwhile, the army regulars all standard issue spears, helmets, and matching supply satchels. Inside the bunker, the occasional twang of a bolt shot from the bunker at a brave attacker.

Ice-Driller swam towards the decapod that was banging out orders. “Captain, I need a word.” He yelled.

“Captain’s dead.” the Lieutenant said. “Who the hell are you?” he asked and fired off an . Ice-Driller returned his visual identity, which the lieutenant did not recognize. “Get back under cover civilian!” He ordered and turned away and rapped his order hammer on a metal plate. .

“Wait! I’m a scientist with a way to stop this war. I need to get to Deepvent!” Ice-Driller said. He glimpsed the carved name plate on the officer: Sharp-Tooth.

The lieutenant looked over the duo with a complex expression and flashed blues. “Are you a scientist with krill-for-brains? We’re surrounded. Did you just dive in a moment ago?” The lieutenant said, more than asked.

“YES! I descended from the ice water. Past the siege platoon above that’s bombarding you. Is the path to Deepvent open?”

“No. We’re cut off. They will kill any fleeing refugee outside the lines. I don’t know who you think you are, but the enemy ain’t going to listen to ‘science.’ They only care about the hard physics of a blade being thrust.” The lieutenant said, holding his knife in a free hand. This caused nearby soldiers to raise their spears and clang them together.

Ice-Driller didn’t think progress would be forthcoming, but still asked. “Can you get me and my crew over the lines to Deepvent?”

“If we could get back to Deepwater, I wouldn’t be here krill-head. What could you possibly have that would impact the battle, anyway?” Sharp-Tooth said.

“An alien weapon. A self-moving metal building from the Overworld.” Ice-Driller bluffed.

“That’s rich...” the lieutenant said.

“I know that's hard to believe, but—”

“If anything helps us survive another tide, I'll believe.” The Lieutenant's war weariness left him susceptible to any hope. “Well, where is it?”

“It is in the city center, near the vent—”

Both had a sudden white-out as an echo-location jammer from the enemy line swept over the nearby bunker and at them. Perception returned to sounds of “Incoming!” / “Cover or be bait,” scatter voices yelled out. Through the deafening, blindness groped their way back under cover.

The enemy noisemaker stopped just in time to hear the dings of long metal flechettes strike the hard surfaces all around them.

A shriek of pain then, “Medic, I’m hit!” a militia cried.

A medic swam over to the hapless decapod. “It’s only his foot.” He called back to his leader. “Fat-Foot here will be fine,” and he cut the metal spike out.

“He’s got nine more!” One regular replied. A quick but tired chuckle erupted other soldiers, the dark humor that fills one's mind to keep the terror at bay. The calls of various orders were heard from the plaza: “Collect the darts!” / “Be quick.” / “Resupply the bolt shooters.”

“At this rate, we’ll be fully stocked on ammo while Fat-Foot there will still have one good foot left,” someone yelled. Another heavy laugh came from the plaza.

Ice-Driller tried to recapture the attention. “Lieutenant, proof of alien life or technology might end the war. Other oceans to live in, or something to unite society against.”

“If I can’t use it in the next hundred moments, it's of no use to me. Begone civie.” Sharp-Tooth yelled.

Just then, they heard the whistle of a bunker-buster. An inverted cone of dense stone rode a super-cavitating bubble of air down. It squealed through the water and found its target by luck, hitting the main bunker destroying half of a back wall. A deep thump reverberated through the water, pounding at the internal organs and those inside the bunker. Ice-Driller could feel it on every foot, though the sound was too low to visualize, but the strike was unmistakable through the water. Items were flushed out from the building’s crevices.

The lieutenant looked back at Ice-Driller. “If you got some alien weapon, then feel free to fight your way out to Deepvent. I got nothing to spare.” At that he left Ice-Driller and went into the plaza.

“Silt incoming!”

The leader blew water through a noisemaker to alert his troops. “Prepare for assault,” then rapped out another order with his hammer.

Ice-Driller swam away back up to Study-Up, who had stood her ground under a doorway. “We’re on our own.” was all he said. They swam away fast as the slow fall of silt muffled the scene behind them. The shrill cries of battle, and the clang of metal on metal, became mute as the sand fell and the two decapods sped away.

They swam away from the deteriorating situation. Back towards Shells and More. Ice-Driller silently halted under cover. Fresh blood in the water!

A to light up their surroundings.

They visualized a decapod ahead of them skewed in the middle of the street. Two long darts had impaled the body. One heart continued to beat and cloudy blood billowed out from the body.

The morbid sight motivated them on, and they stayed safe by the overhangs and eaves.

“I'm an idiot...” Ice-Driller said. “To think the Academy was still in control.” The scent of nearby death had not yet faded from their nostrils.

“The people just want to survive,” Study-Up replied. “And this is a fight for survival.” The military elites had a strange relationship with the scientific leadership. On one arm completely supporting of advances in metallurgy and chemistry, but derided all the theoretical arm-wrestling the intellectuals did.

After a few more deserted streets, they arrived at the central plaza. The plaza was positioned directly over Smallseep's vent. Light industry was on the level immediately above the main agricultural area. They could feel the beat of production below them. Around the plaza were stylish houses and warm water, but devoid of life. Either their population had already fled, or their inhabitants huddled frozen with fear in the homes.

“Warm water!” Study-Up said.

The slightest tinge of relief cut through the overall doom. Ice-Driller and Study-Up easily found The Object as it noisily scanned the surroundings. “It’s searching for the vent.” He said.

“We projected the ancient picture of a natural vent. It is still searching for that ‘natural’ image. Here we are diffusing the heat across several blocks.” Study-Up added as it scanned the tops of the nearby buildings.

The Object was quite fascinating. It navigated flawlessly, and it knew it was near the seafloor and continued to emit pings as it visualized the area. It swam by spinning and was methodical in its sweeps of this portion of the city. “Amazing isn’t it?” Ice-Driller muttered to Study-Up. He emitted another ping towards the machine and watched the reply.

“Amazing—but potentially useless… Well, what now? How do we swim over the battle lines to Deepvent?” She asked.

Thermal-Rock and Sand-Stirrer swam out from under cover from across the plaza. They recognized their voices. He didn’t even flash an . “Any news?” They yelled loudly. The yell that was overloud for the short distance.

“No, we’re surrounded, and the military can’t spare anyone to escort us.” Ice-Driller said.

“That’s what we surmised from the locals, but we discovered something—” Sand-Stirrer started.

“Yes, The Object can be induced to emit a deafening sound.” Thermal-Rock added.

“All we need to do is reproduce the same sound-image from two different angles and it will emit a loud ping. We can show you! We were blind for at least a hundred moments.” The two decapods swam away towards The Object.

“Come back—I believe you!” Ice-Driller said. “So that’s the plan. Try to deafen everyone as we pass over?”

“They’ll still shoot at the source of the noise.” Study-Up stated.

“Just be far enough away from it and nothing will hit us.”

They tied up their cargo on The Object since it did not seem to be weighed down by their little mass, the Overworld Stone, the experiment, and the sono-pictures were almost buoyant compared to the machine’s mass.

Study-Up flashed danger blue, “this is a terrible plan.”