Previously, in Pokémon: The Lost Child, Aegislash continued to be suspicious of Greninja but was unable to prove that they were up to anything. Aegislash, unknown to him, had helped Greninja realize their ultimate plan. Before Aegislash could uncover anything else, he was called over to check out a mining volcano that went radio silent.
Aegislash arrived at the volcano. The first thing he noticed right away was just how empty it was. There weren't any Pokémon in sight. Aegislash doesn't exactly visit this place often, but he has been here a few times and it was swarming with Pokémon every time. Darkrai was right. Something very bad had happened.
Aegislash went deeper inside the volcano and eventually discovered one Pokémon. It was a Camerupt, Aegislash knew that there wasn't a Camerupt that was part of the Brotherhood, so the fact that this was the only Pokémon inside this base was even weirder. Camerupt seemed to be doing something, but Aegislash was unable to tell exactly what he was doing.
Aegislash wasn't sure how he was going to approach this, as as of now he didn't even know what the intentions of this Pokémon were.
Aegislash decided to just approach casually and ask, "Hey, what is going on?"
"Oh, it looks like one of you survived," Camerupt said while turning around.
"Survived? What are you talking about?" Aegislash asked.
"My plan is nearly complete I have eliminated anyone who stood in my way. All of the Pokémon inside of this place, let's say that they are all dead," Camerupt responded with a response that even terrified Aegislash.
"That is a force shield. I know these things," Aegislash commented after noticing the device behind Camerupt.
"This thing will trap everyone, and then this volcano will go boom, but you won't survive long enough to see that," Camerupt, after saying that turned on his force shield, trapping 3 separate villages inside. Camerupt then launched a flamethrower at Aegislash, which caught him off guard. Aegislash dodged out of the way of the flamethrower and launched a shadow ball at Camerupt.
Aegislash then leaped in to duel with Camerupt with his sword, but Aegislash had vastly underestimated Camerupt's strength, and he easily took the sword hits and burned Aegislash with another flamethrower. Aegislash did not take it well and started limping on the ground. Camerupt was ready to finish Aegislash off, but Aegislash launched a shadow ball into his eye-blinding Camerupt, so Aegislash was able to escape.
Little did Aegislash know that Empoleon and Sceptile also happened to be in one of the villages when the force shield was activated and was ready to leave.
"Well, it's been a fun time. See you all later, hopefully," Empoleon said as the two were leaving. While Empoleon and Sceptile were walking away, ready to continue on their journey, Sceptile was stopped by some kind of force and said, "What in Arceus' sake was that."
Sceptile tried to go through it again, only to be stopped again. Empoleon also tried to walk through but was getting stopped by some kind of force and commented, "That is odd. Why can't we move past this." Empoleon and Sceptile started feeling around and quickly realized that something was completely encasing this area that prevented them from leaving.
"I don't understand what is going on?" Sceptile commented.
"You don't know what this is?" Empoleon asked.
"I do not know, unfortunately, the best I am getting is that there is some sort of barrier covering all three of these villages that are preventing us from leaving," Sceptile responded.
"Why would there be one?" Empoleon asked.
"That is a really good question," Sceptile responded.
Empoleon and Sceptile were hanging around trying to figure out what to do to get around this. During which, Aegislash approached their direction, still somewhat injured but slowly recovering. Empoleon and Sceptile heard someone approaching and turned around to see Aegislash. Instantly, Sceptile rushed forward ready to attack while saying, "This is your doing, isn't it?"
"While I can see why you think that, I swear this time this is not my doing," Aegislash responded.
"Do you seriously think that we will believe you?" Sceptile, while talking, tried to attack Aegislash but Empoleon stopped him, telling Sceptile, "He looks genuinely injured this time, I hate Aegislash as much as you but we should hear him out."
"Ugh, you better have an amazing explanation, Aegislash," Sceptile responded.
"That I can provide you."
Aegislash told Empoleon and Sceptile everything that had happened with Camerupt, what he saw, and why he was like this.
"Camerupt wants to blow up that volcano over there. It will wipe out these three villages and everyone inside," Aegislash finished off.
Empoleon and Sceptile were stunned by this, with Empoleon immediately jumping in to say, "We need to stop this before thousands are killed."
"I guess we don't have a choice since we are trapped in this place," Sceptile said in response.
"I'm glad to see that you two understand the full stakes of this situation. I know that we don't exactly like each other, but if we want to stop this, I suggest that we team up," Aegislash said.
"That is totally out of the question," Sceptile responded.
"Look Sceptile I understand why you feel this way, I hate Aegislash as well for what he has done, especially to Magmar. We need his help though," Empoleon said to Sceptile.
"Listen to your partner. If you don't let me help, then we all die together," Aegislash said in no uncertain terms.
"Ugh, fine, we will work together, Aegislash. Let me be clear: as soon as this is completed, we will be enemies again," Sceptile stated.
"I wouldn't expect anything else," Aegislash responded.
Aegislash has now formed an uneasy alliance with Sceptile and Empoleon. Once, great enemies, they are forced to work together to fight against a common enemy. The three snuck back inside the volcano. Camerupt was still hanging out around there. Now that the three of them knew what to look for, they noticed that Camerupt was using some machine to pump magma directly into the volcano. Magma that he was primarily making himself, which he was planning to use to overload the volcano so it would erupt.
It was a horrible plan that completely disgusted Empoleon and Sceptile, Aegislash didn't like it either, but he was more concerned about his safety and the potential loss of valuable resources. Empoleon and Sceptile couldn't help but wonder what Camerupt's motive was. Doing this doesn't have much of a tangible benefit. They didn't have much time to focus on that, and they needed to stop Camerupt.
Empoleon launched a powerful water gun at Camerupt while his back was turned. Camerupt was hurt rather badly by this and turned around to see what was going on.
"Your evil will not be allowed to spread!" Empoleon shouted.
"You can not stop me. My plan is already in motion. These villages will burn to the ground, but it won't stop there. I will continue from volcano to volcano, there are many for me to use after all," Camerupt responded.
Empoleon and Sceptile were horrified and disgusted to hear that Camerupt was planning this. Now that Empoleon got a closer look he noticed something. The volcano on his back is the same description as Weavile gave to the killer of her parents. It couldn't be a coincidence.
"I believe I have heard of you before. You are the one that murdered two Weaviles weren't you," Empoleon said.
"I'm surprised that you know about that. Yes, those two were my first kills, and I still remember the rush of killing; it was so much fun, and the thrill is something I'll never forget. It won't as now you three will die," Camerupt responded.
Camerupt launched a flamethrower at Empoleon, which he countered with a water gun. However, this time the water gun was even bigger than before, a size he had never managed to pull off before. The new massive water gun destroyed the flamethrower. While this was happening, Sceptile snuck up from behind on Camerupt and hit him with his leaf blade, while Aegislash hit him with a shadow ball. Camerupt was able to launch a massive eruption from himself that rained fireballs from himself, though Sceptile and Aegislash had to dodge out of the way.
Empoleon went closer to Camerupt to face him in direct combat with metal claws while Camerupt was shaking the ground with a massive earthquake that was hurting Empoleon badly. Empoleon kept pushing through that and attacked Camerupt with his water attacks, which were hurting Camerupt extremely badly.
"You are proving to be a much bigger nuisance than all those Pokémon I killed to get inside this place," Camerupt commented.
"That is what the power of teamwork does." Empoleon, as he was talking, launched bubbles at Sceptile, who used his leaf blade to launch them at super speed at Camerupt, each of them hitting Camerupt for massive damage. Aegislash was doing the same thing, launching shadow balls which Sceptile would launch towards Camerupt.
Camerupt, by the end, was weakened very severely and was barely able to fight anymore. Camerupt was eventually hit so many times that he fell into the lava of the volcano. The three thought that was the end of it, but when they looked at the bottom of the volcano, they saw that Camerupt was still alive and he had a plan.
"If I can't survive this encounter, then nobody can." Camerupt used a massive explosion to blow himself up. This explosion caused the entire volcano to collapse in on itself. The eruption of the volcano was beginning and the three knew it was going to be bad.
"What do we do?" Empoleon asked while panicking.
"There is nothing we can do anymore. We need to get out of here," Sceptile said.
While they were talking, Aegislash destroyed the machine powering the force shield and, along with Empoleon and Sceptile, fled the volcano before it erupted.
"We have to warn the Pokémon in the village," Empoleon commented.
"We have to hurry though. I will take one and you take another. Hopefully, we will have enough time to warn the third," Sceptile responded.
Empoleon and Sceptile hurried over to the villages as quickly as they could and warned the residents about what was about to come. The residents started fleeing the town as fast as possible as the volcano erupted and the lava from it was approaching faster and faster. The residents were able to mostly evacuate the areas, with thousands managing to escape. However, it was not all good news. There were several dozens to hundreds of them that weren't able to get out in time.
The villages there mourned the deaths of their fallen brothers, and Empoleon and Sceptile joined them.