"Can't we just forcibly take them prisoner?" Duchess Euklid requested to Styx with her head bowed down subserviently.

Styx sat upon his throne in the ocean pagoda, all the dungeon wives sitting on thrones along with the latest wife, Everest, whose throne had to be enlarged greatly to match her giant size.

"Do you intend to disrespect the Duke and Duchess even until the end?"

Duchess Euklid had lived inside of the dungeon for the past week out of concern for her former friends who were adamant about never abandoning the kingdom.

"That's not…"

"It is. They hold the resolution to perish alongside their rule over the dungeon city. They are truly stubborn and have even been sending out evacuation orders to all the citizens, hoping to serve the kingdom one final time."

"…"

"Respect their loyalty. They will die, but their heads will be held high until the moment it leaves their shoulders."

Duchess Euklid bit her lip hard enough it drew blood. She had constantly been petitioning to talk with the nobles ruling Lagoon Porter City, to get them to change their mind, but Styx had been just as determined to do things his way.

"Return to your home and pack your belongings. I understand you want no part in this event, so I will be sending you back to your dungeon city to make arrangements for it to come under my banner. Convince your husband or take over the ruling position. You understand what is to be done if he doesn't surrender, right?"

"…Y-yes."

Duchess Euklid bowed her head one final time before heading back to the residential town, where her daughter, Rebecca, was drinking with a group of tiger beastmen.

~~~~~

⠀

"Lassie, you look like you could support an entire streak of cubs," One particular giant tiger beastman with bulging muscles placed his arm around Rebecca's shoulder, his hand hovering just above her large breasts. "Why don't you pair up with me, I promise to look after you well."

"Sorry, but I am reserved for Styx himself."

"M-my apologies, mistress!"

The tiger beastman quickly stepped away from her and bowed in apology, creating a stark contrast in appearance as Rebecca's head was only at the height of his chest.

"Don't worry about it, I am friends with everyone," Rebecca giggled and lightly slapped her hand on the beastman's chest jokingly, the large man not daring to defy her. "You beastman are oddly respectful of Styx though, you should be more casual."

"That is impossible, mistress. Lord Styx is the Great Dungeon Lord Who Rules Monster Lords, and his might is undeniable."

"He isn't all that powerful himself, though?"

"Power is not always in the strength of an arm. The people one rules are also the power of the ruler. To defy the hierarchy is to be banished."

"Have many been banished?"

"There have been a few, Mistress. An old brother of mine also didn't recognize Lord Styx's power and turned his back on us. We erased in place of Lord Styx to protect the group."

"I see…" Rebecca nodded her head nonchalantly whilst admiring the beastmen's loyalty.

The beastmen had a domineering self-policing culture in that those ostracised from the group could either never return or were killed depending on an independent evaluation. This was gradually expanded to anyone who was a part of the dungeon, but none took this more seriously than they did.

Styx had never had a problem with this and allowed it to take place. He held no desire to protect those who refused to be his and held an even more cold-hearted attitude towards anyone who betrayed him.

"Daughter, here you are."

Several tiger beastmen and a couple dark elves made way as Duchess Euklid entered the group along with a strange woman.

"Mom?"

"I am heading back to my city to… arrange its surrender."

"That is for the best. I don't want to see father die, after all"

"…Daughter, you have changed."

"I'm just being true to myself. For once, my heart and my duty are aligned, so it is much easier for me."

"Are you coming back with me?""I am yet to give myself to Lord Styx, so I need to remain. He can send me back if you need me there, Mistress Aura can get me there very fast. Who is this?"

Rebecca looked towards the woman whom she had seen a couple of times within the dungeon on the training field, but she was a part of the forest exploratory group.

She was a Third Step female tiger beastman, but had utilized Styx's new public breeder method and managed to evolve. Rebecca wasn't sure how she had done it, but the female beastman had become much more human like, with reddish brown hair cropped at her shoulders and tanned skin covered in tattoo-like tiger stripes.

"This is the leading fighter of my guard. Whilst I am by no means weak, she is much stronger than me. The others are about as strong as me too."

"Is that needed?"

"Styx believes so."

"Before you leave, you should have Styx help expand your mana network. I've told you all about it, mom, it will help make you stronger."

"…Becca, I also know what I need to do for that."

"Don't worry, you will be well looked after. You are at your Max Level aren't you?"

"…"

"Come on, we will go to my home and do it together. You don't need to worry, mom, it's not Styx himself but a device, so there is no infidelity. Plenty of the couples in the dungeon use them."

"…"

Rebecca's expression rapidly lit up and she bid farewell to the residents she was spending time with and dragged her mother by her wrist. Edna Euklid was stronger than her daughter, but she hesitated and gave her a chance to overpower her.

Contrary to first appearances, Rebecca Euklid was currently a Second Step Brawler, a class which fought with their fists directly and had a high dexterity too.

Her strength and mana pool had been rapidly increasing ever since she begun staying in the dungeon, so it was natural she would want her mother to also experience the same growth.

The evolved female tiger beastman grinned and followed along in high expectations of using a breeder. She used her own whilst Rebecca had some more forceful mother daughter time which gave Edna a memory she would never forget.

~~~~~

⠀

The underground tunnel connecting the dungeon to Lagoon Porter City was on the verge of completion.

Styx could feel the boundary of the dungeon that the city was just ahead of him via a dungeon extrasensory perception. It was like a thin film that loomed just ahead, and the only way through was by piercing into it.

"It's time," Styx casually commented whilst standing in the dungeon with hordes of monsters and Aura behind him as well as lots of participating dungeon residents.

He clenched his fist and used his dungeon mana to directly excavate the remaining wall of dirt, officially entering into the dungeon city's territory.

⠀

[

Warning! Dungeon conflict detected!

⠀

Now opening Invasion Mode, all summoned monsters will be hostile to invading/invaded dungeon. During this time the Limited Shop will open, allowing both parties to purchase supplements to invade and defend.

⠀

Limited Shop opening…

Dungeon Territories merging…

Monster hostility allocating…

Dungeon Experience doubling…

⠀

Dungeon War commenced.

]⠀

A notification opened up in Styx's head, while he assumed a similar one had appeared before Duke Ashburn.

The tunnel had opened up into a giant cavern which was the same dungeon Therina entered whilst she was in the dungeon city. The actual dungeon was the entire city above, but just as Styx could extend up into the aboveground area, the open dungeon that was the city could also dig down.

Styx's dungeon type was actually the rarer kind in the infinite world as it was easier to expand in the open world rather than having to excavate everything.

Roars of various monster echoed out throughout the dungeon below the city, the simplistic and widely open structure of it causing its source to be unknown.

Not long after, hordes of monsters charged at the invaders who were spilling out into the dungeon. Styx had the Obelyon Mana Gauss Cannon installed at the entrance and loaded with 50,000 mana points.

As Styx was invading from the second floor of the city's dungeon, the immediate monsters were all weak and of the First Step. Half of Styx's monsters were at the First Step too, but they all had strength close or equal to a low Second Step ranker. The other half were Second Step monsters and were even more powerful.

The more powerful the dungeon residents became, the more powerful monsters they bred for Styx. Even his immediate dungeon wives were giving birth to monsters that were of the Second Step the moment they reached adulthood.

Styx's monsters utilized tactics under his control, many equipped with steel weapons or armor too. They tore apart the defending monsters effortlessly with thorns, blades, and teeth. Blood spread out from the defeated monsters before they evaporated back into the mana the were born from, leaving behind small mana gem shards.

The tiger beastman and elves strolled through the dungeon like they were sightseeing. Any monster that got too close to them was instantly killed.

"Hmph, the duke can't even control you basic summoned bastards, what hope could you have of winning. Aura, how is the barrier?"

Aura nodded her head and responded, "It is covering the city. They won't be able to escape now."

Above ground, a violet barrier powered by Aura's Phantasmagoria covered the entire city. The regular citizens looked up at the purple oil like barrier covereing the sky and panicked whilst the adventurers and mercenaries all clenched their weapons.

They had all seen the evacuation warning from Duke Ashburn in the guilds and public squares, but only half of them had left the city. Some were still contemplating whilst other had their entire lives based in the city and felt the inability to leave.

Styx didn't care about the people that left. He could have Aura or Everest seal off the city, but he was intending to take over the entire kingdom. Even if they ran, they wouldn't be able to escape him.

~~~~~

⠀

Duke and Duchess Ashburn sat in a tall, guarded barracks before an enormous glowing blue prismic gem several meters from tip to tail. Contrary to what the city residents believed, the dungeon core of the city wasn't kept in the duke's mansion, but in the heart of the city guard.

This was irrelevant to Styx though, as he could feel the location of the core the moment he began the dungeon invasion. The duke wasn't a dungeon core so he couldn't feel the location of his core, but the summoned monsters could.

"How is it?" Duchess Ashburn asked whilst looking out the window at the violet sky with worry.

"…It is as expected, we will not be able to hold on for long."

"The city defenses!"

"I will turn the cannons on the heart of the city, but they could dig out through anywhere. Dungeon cities aren't designed to defend from dungeon invasions after all…"

"Is there nothing we can do?"

"Dear wife, they have not one, but two Monster Lords. We can only do as much damage as we can and give the kingdom more time to prepare. Hopefully, means of defending from dungeon invasions will also quickly be solved. I have already sent a final emergency notice to the capital."

"It's not all bad though, is it?"

"What do you mean?"

"The heart of the demon invasion is heading straight for this area. If it grows fast enough, that dungeon will become a buffer zone between the kingdom and the demons."

"Oh! I hadn't even thought of that! Hahahaha, guards!"

Several heavily armored guards clamored into the room, their weapons held poised to defend the duke with their life.

"Duke?"

"Pass on the message, have the city cannons retracted."

"Duke!"

"You heard my orders. Hurry up."

The duke's wife looked at him with a concerned gaze and clenched her fist, "Are you sure about this?"

"Of course. I hadn't though about it, but this will give the king some much needed breathing room with the invasion. I can't have the dungeon too heavily injured now, it would slow down its expansion too much to stop the demons. It looks like I have one final emergency communication to make."

"But what if the dungeon sides with the demons and lets them through."

"That is impossible, those bloodthirsty demons don't compromise with anyone, even themselves. If the dungeon lord wants to live, he will have to fight off the demons with everything he has."

The duke broke out into another grand bout of hearty laughter, his deep set voice echoing in the room.