When Cecil resurfaced, he quickly jumped onto the boat which had remained in the same place as before.
He couldn't help but notice that there were some monster carcasses on the boat and that the boat had expanded in size and there were now some tents laid about on the ship's deck.
When everyone saw the water burst apart and that something had landed on the boat, they all raised their weapons before lowering it once again when they saw that it was just Cecil who had finally returned.
"Master!"
"Cecil!"
"Brother-in-law!"
"Lord Cecil!"
Ren, Celestina, and the two leaders of the Revertia and Regulus Kingdoms' groups quickly walked over to him. They seemed quite relieved to see him again.
"Master, what went wrong? Why did you take so long just to clear the monsters?" Ren urgently asked.
He noticed that there were no injuries to his master so it was probably not something major. As for why he had asked this question, this was because Cecil had disappeared for quite some time.
"What? I... How long was I away?" Cecil asked back in confusion.
"You were gone for almost 2 weeks..."
"What? Two weeks?!"
Everyone had thought that something bad had happened to Cecil after 3 days had passed by with no news from him. So they had sent a team down to the city ruins to check on him. When the team had arrived and saw that there were still monsters teeming within the underwater city, they thought that something terribly wrong had happened or Cecil had been forced away from the city without their knowledge.
When Cecil heard about their worries, he lightly laughed to himself. He didn't think that his 'quick' training session 10,000 meters beneath the sea had actually taken nearly 2 weeks instead of the short one or two hours he had felt.
"So...you went to train?"
"Yeah, it was a good opportunity to raise my power. I just didn't think it would take that long," Cecil replied to Cecilia's question.
Cecilia nodded thoughtfully to his answer but looked a little bit confused. Karen who was on the side gave voice to her confusion.
"Raise your power? But, Lord Cecil...how come your mana level dropped instead? Also, I can feel that this is a permanent drop, not a temporary one..."
Cecil chuckled and waved his hand, not wanting to answer.
"Don't worry, I may have my mana levels lowered, but I'm much stronger now. I had to sacrifice something to get something better."
"Hmmm, I see. Anyway, shouldn't it be time for us to leave now? We had been luring out some monsters from the city during the past few days so there shouldn't be too many left!" Karen said.
"So you guys were luring monsters out of the city? No wonder when I moved within a hundred meters of the city those monsters came rushing out. You guys had been harassing them!"
"Hey, don't make it sound like we did anything bad! We were going to kill them anyway!"
"Well, let's finish the job then!" Cecil said with a grin.
He walked towards the center of the boat's deck and released his mana. A golden aura was ejected out of his body and the large ship was encapsulated within the golden sphere of mana that Cecil created.
"W-what's this?"
"This...this doesn't look like a barrier..."
Many in the group were surprised to see the golden sphere that surrounded the boat they were on, in the next instance, however, they turned even more surprised when the boat began to dive underwater.
"!"
"WAHHH!!"
A few of them were scared and shocked at first with the sudden development, but when they saw Cecil's golden sphere repel the water away from the boat, they immediately felt relieved before feeling a bit curious.
With his new upgrade, Cecil was now able to manipulate and control his mana to a finer degree. He used his mana to form an aura around the boat which would be able to repel the water and just by using his mana he moved through the water.
Before, Cecil had been using the skywalking technique that he had acquired through his pact with Silver to fly through the sky, but now that he was able to use mana to this degree, he was confident that he could agilely fly through the sky without wings just by using his mana like he was doing now.
Wrap mana around his body and use the mana to move. He sorely wanted to test this out right now, but he had more important things to do.
Another change that Cecil felt from his body's upgrade was that now, unlike before, his body was not only able to create Ki, but it was also able to create mana.
The equilibrium of his two energies had probably strengthened after his body's recent upgrade so that now, his Mana point behaved just like his heart. It could create mana just like how his heart could create Ki.
He no longer needed to recover his mana by taking in the ambient mana from his surroundings and pulling them into his body. Instead, his body acted as a mana source which could generate its own mana.
This was a welcomed upgrade since now he wouldn't be able to completely exhaust his mana if his body continued to constantly generate it. This also meant that his mana recovery would be much quicker than before.
Cecil cleared his thoughts and focused his mind on the task at hand. When they arrived closer to the underwater city, he immediately detected the monsters change in activities. They had detected the approaching human ship and were moving to intercept them.
"Everyone get ready! Mages, you can shoot your spells through the barrier so start chanting! Ren, the sharpshooters, and any other archer or long-ranged fighter, prepare to attack! Just shoot through the barrier, it won't hinder any of the attacks going out, but it will stop any attacks from coming in! So don't worry about your defenses and just focus on attacking!" Cecil commanded.
The three leaders of the groups quickly began organizing their people after hearing his words. Karen had her mages and archers ready to attack, while Cecilia gathered together her priests and mages.
Ren and Celestina organized their group's sharpshooters and mages. Once everyone was ready, Cecil sped up and the two forces, the monsters, and Cecil's group, quickly collided.
Cecil's barrier was able to smash away any monsters that tried to approach. From within the barrier, spells, arrows, and magic bullets began flying out. The monsters which were just about to collide with the barrier were all blasted backward from the attacks.
The front-most monsters immediately received fatal injuries and if they didn't directly die, the impact of being hit by Cecil's barrier which came to them in the next moment since Cecil didn't stop moving forwards directly killed them.
"Keep it up! Don't worry about the barrier. It won't be breaking any time soon!" Cecil cried out before continuing in his mind.
'Or at all for that matter.'
It was an arrogant thought, but this was because Cecil had confidence in himself. As long as he supplied mana to the barrier around him, it wouldn't break or falter. Especially, not from the attacks of these underwater monsters which were at best S-ranked.
Cecil didn't forget to hurl out a few Mana Volleys and Flash Cannons along the way. The ship bulldozed through the waves of monsters until it broke through what seemed to be a thin film that encapsulated the outer floor of the city.
When they broke through the thin film, Cecil immediately took down the barrier since the monsters had all stopped chasing after them. Past the barrier, there was no longer any water so it was only natural that the underwater monsters didn't pursue them.
Cecil gently landed the ship in the middle of a ruined plaza and dispelled his barrier.
"Now that was some good exercise!" Cecil chuckled.
"How magical, there's a thin layer of mana protecting and keeping the water away from the upper stratum of the underwater city," Celestina remarked curiously.
"This city...doesn't it somehow remind you of those sky fortresses from the Machina Empire?" Karen spoke up after taking a look around.
It was apparent that Karen had once visited the Empire since she was familiar with the structure of the sky fortresses.
"That's right, Karen, this indeed reminds us of those sky fortresses," Cecil said.
"...That's because this is a sky fortress, isn't it, Master?" Ren added.
Cecil nodded at Ren's words. If anyone could recognize this, it was undoubtedly his disciple. Ren had been living in a sky fortress for nearly half of his life so it would be odd if he didn't recognize this city's structure.
"Why would there be a sky fortress here?" Celestina asked.
"The sky fortresses were originally not something the Empire created. They scavenged the 51 fortresses from an ancient ruin a long time ago. Many outside and inside of the Empire have forgotten about this ancient history so most people believe that the Empire's artificers and engineers created the fortresses when in fact, they didn't..." Ren replied.
"W-what? Then what's all that hubris about them creating more sky fortresses and those ancient weapons?!" Karen exclaimed.
Ren shook his head, denying Karen's words, and continued, "The sky fortress blueprints that are in the hands of the Empire are complete but because the materials to create the fortress are no longer accessible, it's only natural that they can't build it. However, the creation of some ancient weapons is indeed true."
"...Kid, you sure know quite a lot about the Empire."
Ren turned mum after Karen's remark. He shrugged his shoulders and began looking around the place.
Karen turned to look at Cecil, clearly asking for more answers, but Cecil didn't respond despite Cecilia and Celestina's gaze also honing in on him.
"Less talk and more exploring. I already found the transfer gate's location, but we have to get there on foot and not by force. I don't want to risk any of my attacks damaging a critical structure that'll activate the gate," Cecil said before walking away.
He had already spread his Mana Sense out and quickly found that there were no monsters present.
"Hey, what are we looking for?!" Karen asked.
"Find a mechanism that'll lead us down to the floor below us! The sky fortresses use gateways to travel from floor to floor so go and find some kind of archway or magic array!"
Leaving behind those words, Cecil began to explore the place in earnest. A few good things were lying around and Cecil thought that it would be a waste to just leave without taking them away.
He had already found the gateway to the next floor, but he thought that maybe everyone needed a rest. They had been combating monsters for the past week and a half so they could use some downtime.
The rewards were also beneficial for everyone and they didn't need to be told that there were some treasures here that could be obtained. With everyone either taking a rest or exploring the ruined city and obtaining some kind of reward, they didn't see the pair of purple eyes glaring at them from far away.