Rishia thought back to before she joined Itsuki's party. She lived with her family who despite being impoverished were very happy. But those happy days ended when a nobleman from the neighboring town raided her parents home and attacked them, over debts illegally levied on them with no means of paying them back. So the nobleman took her as payment, and kept her in his dungeon devoid of all hope until the day came when Itsuki rescued her and revealed the nobleman's evil to everyone, causing her to fall in love with the Bow Hero. Now we move to the current point in time as it was nighttime at the coalition camp as Rishia was telling the girls the story of how she came to be part of Itsuki's party.

"Oh dear god, I wouldn't even imagine how that must have felt." Sachiko said.

"It was like how my parents were killed. Well, without the whole 'sold to slavery' part." Rinwell said.

"That man certainly had no right to be called a noble if he committed such fiendish acts as that. Serves him right!" E. Constance said.

"Now I'm really glad you were permitted to join the guild. I know what it's like to be alone." Kat said. "At first, I had no recollection of who I was before or why I have these powers, but it's thanks to Ethox and the others I found a place to belong and friends to be with." she smiled as Dusty meowed.

"Lord Itsuki saved my life and the lives of my parents. So I want to repay him… I want to help him." Rishia said.

"I may not have the right to say this, but…" Ost started as she held both of Rishia's hands in hers. "I'm sure he's safe."

"Thank you!" Rishia said.

Raphtalia's ears twitched as she turned to see Naofumi and the group leaders approaching.

"Having some girl time, I see." Hope said.

"Rishia wanted to share her story about how she met Itsuki. You wouldnt belive how much she admires him." Mahiru said.

"He saved her and her parents both. The one time we've heard so far he's been an ACTUAL hero." Lei mentioned.

"So what's the plan, guys?" Hapi asked.

"We leave at dawn. For the back of the Spirit Tortoise." Naofumi said as everyone turned to the mountainous region on the creature's shell.

"We're seriously gonna mount that thing?!" Kazuma asked as the group headed out. "Why exactly?!"

"We missed something when fighting the Spirit Tortoise before. Just because we decapitated it yesterday doesn't mean it died. The fact that it still lives shows that we need to strike directly at its heart in order to kill it." Ivy said.

"Wait, so we're actually gonna go inside the thing? How?" Subaru asked.

"While Kat, Kumoko, and I were scouting the big guy, I noticed some ruins on that thing's shell. That suggests people actually lived on top of it a long time ago." Ty said. "And if there's a whole mountain on its shell, then there must be a system of caves in it."

"And those caves must be a maze that goes all the way down into the inside of its body!" Luz realized.

"God, as if going inside the Great Maw wasn't enough…" David sighed in annoyance.

"Yeah, that was gross…" Glimmer said.

"Say Ty, you and Kat have been pretty tight ever since she joined up with you guys. Any reason why you two and Kumoko are together?" Mahiru asked, trying to make the subject lighter.

"It's because we decided to form an Adventurers party," Ty said. "I've been on my own for a while, and I thought I could step up my game by building my own party. Seeing as Kat was still new, I figured why not team up and see where it leads?"

"And I just tagged along," Kumoko added. "There was really nothing else for me to do. Better than just sitting around and spinning webs all day."

"And…what about the new threads?" Kazuichi asked, noticing that Ty was wearing some black track pants and a black hoodie with the emblem of the Great Tomb of Nazarick, and by extension the Sorcerer kingdom on the back.

"Merchandising," Ty replied. "Kaze was selected to represent the Dungeon Knights during the Auction, but I was roped into being a poster boy for the Sorcerer Kingdom."

"I'm kind of surprised Ainz and the others were on board with this." David said.

"Well he technically isn't a normal human. An immortal one like him has the right to share in Nazarick's power." Ainz said.

"I'm more surprised you're good with hanging around the more monstrous members of the guild, Ty." Hope said.

"Hey, I hung around supernatural forces before joining this guild, what can I say? I know my crowd." Ty replied.

"Yeah, he even had his own group at one point, remember?" Mayumi asked.

"How can we forget? It did split apart due to the aces leaving though." Hope said.

"Wow…thanks for bringing up my low point." Ty said.

"Yeah, it's kind of Hope's thing. Kind of makes his name sound a bit deceptive." David said.

"Anyway, right now, it's just me, Kat and possibly Kumoko." Ty said. "I might have eyes on a Fourth member, but that all depends on what happens after this."

"Ah, yeah. Four is usually the number for this kind of thing." Jesse said.

"Actually, there really isn't any limit for adventuring parties." Theo said.

"So, why settle on four then? There's got to be a reason." Takeshi said.

"Games usually settle on that number to make things a bit easier for players playing RPGs. MMORPG's play by different rules when it comes to parties." Ainz said.

"But most parties we know of usually keep to about six to eight in them to make things manageable." Theo said.

"Yeah, we know a lot of ones that are like that. Usually in cases for reserve members or party splits." David said. "Color Gods, I sound like a total nerd…"

"You are a nerd." Subaru and Kazuma said.

"Anyway, like Naofumi said, if we don't kill the Spirit Tortoise, it's gonna revive and we'll have to go through that whole thing all over again." Theo said.

"Which is why attacking it at its heart from the inside is the way to go." Ethox said. "Like Ty said, we'll locate a cave entrance at the mountain on the tortoise's back, and maneuver our way to the heart."

"Sounds like a plan." Balthus said.

"Just one question: How are we gonna get up on top of its shell?" Scarlet asked. "Not everyone here can fly."

"And I can only grab so many things in my Stasis Field." Kat added.

"We'll be using magic to create a bridge to allow others to cross over to the turtle's back." Ainz said.

"Magic, is there anything it can't do?" Kazuichi asked.

"Let's not answer that until there's something that it can't solve, okay?" Entrapta asked.

"Plus, you do know that anti-magic suppression is a thing, right?" Genis asked.

"Genis is right. It can't solve everything." Zelos said.

"But it can get us up on the Spirit Tortoise's shell, apparently." Nemo said.

"We should really move along." Ainz said.

So the party moved onward as they crossed through a rocky mountain and a bridge of magic before making it onto the back of the Spirit Tortoise.

"So this is the tortoise's back, huh? This is gonna be a tough climb." Naofumi said.

"It may take days before we even reach any kind of opening into the turtle's body." Chopper said.

"Wow, it's almost like the Spirit Tortoise doesn't want visitors." Emo remarked.

"Well, it's getting some anyway." Mark said. "The sooner we start, the sooner we get there."

"I just don't understand. I'm a servant of the Spirit Tortoise. My job is to steal souls. So why would you all treat me so kindly?" Ost asked.

"Huh? Why should that matter? You helped us so you aren't our enemy." Jexi said.

"Yes. While it may be true you may go back to your original role when we defeat the one controlling the Spirit Tortoise, you are a kind person regardless." Natyal said.

"When you think about it, isn't what you're doing kind of like going against your own destiny?" Hope asked.

"What do you mean?" Ost asked.

"You were created as a familiar to a beast that was meant to stop the waves as a last resort at the cost of thousands of lives. But even though it went rouge, you chose to ask someone to kill it to save millions, and here you are helping us trying to stop it." Hope said.

"Hmm…perhaps." Ost said as they continued onward.

After traveling all day, they all came upon a decimated village with bodies scattered all over.

"Poor bastards. Must have been living here when the turtle was still sleeping." Kaze said.

The heroes just stood there and offered up their condolences to those who lost their lives atop the turtle's back.

"No more lives are gonna be taken by this thing. We'll stop it." Hope said.

"Like stated earlier, the only way we're going to stop this thing for good is if we destroy the reptile's heart." Kaze said.

"Yeah. Maybe there's a clue to do that around here or something." ZS suggested.

"Hmm…" Ethox scanned their surroundings until he spotted a temple in the distance. "That place looks important. We should check there."

They entered the temple and looked around for a bit.

"Hmm…right here." Garfiel said as he went and broke down a wall in the temple.

"Hey! We're trying to stop the turtle! It's already done…enough…damage?" Theo said as the broken wall revealed a tunnel leading inward.

"There's our entrance to its heart." Yuri said.

"Lucky us…they went and built a shrine where we go down. Let's not keep it waiting." Theo said as they entered the tunnel.

"If I remember right…we must be in the large intestine." Chopper said.

"Makes you wonder…if it eats souls, what's it pooping out?" Naofumi said.

"Some questions are better left unanswered." David said as the conversation was making him nauseate.

"Come on. We were all thinking it." Naofumi said.

"No…no we weren't." Nami said.

"Alert: Three unknown humans detected." 042 said.

"Three of them?" Ethox asked. "Wait a second, I think they might be…guards up!"

A man wielding a scythe came charging in, only for Ethox to block with Way of the East.

"What the?" Theo said as he held up a lantern as three figures were shown. "What the? Adventurers?"

"Oh uh…sorry. We thought you were familiars." the scythe wielding man said as two women were with him.

"What are you doing in this place?" Naofumi asked.

"We were asked by the queen to help you out. Safety in numbers after all." the man said.

"She did, huh?" Naofumi said.

"Well…we'll get out of your hair, kiddos." the man said.

"Kiddo's….wait…" Theo said. "Raphtalia…would you mind…"

"Of course." Raphtalia said as she went and cast a spell and dispelled an illusion concealing the three.

"Oh well….was worth a shot. Nice to see you again, kiddo." the man said, shown to have red spiky hair and a bizarre outfit. Though this man was known well to the adventurers.

"L'Arc!" Theo said.

The two women also wore unique outfits, though one had her face turned away as she held up a closed fan.

"Therese and Glass too!" Ethox said.

"Wait, you know these guys?" Dan asked.

"Uh…remember when I said we may have run into Vassal Weapon wielders before?" Theo said.

"This is them then." Ace said.

"Yeah. We fought them back during Cal Mira Island training. Don't underestimate them. They're strong." Theo said. "Though…why are you three here? Back at killing the other Cardinal Heroes?"

"Try not to look so tense. We aren't here to start a fight." L'Arc said. "See…the guy who removed the Spirit Tortoise seal…we're here to kick his ass."

"So you're after the one behind all this, huh?" Ragna asked.

"That's tight. And you're all here to kill the thing, I'm guessing." L'Arc said. "Pretty sure that aligns our goals, so whaddya say we work together?"

"Why would we team up with people we'd have to fight later?" Michiru asked.

"Cause the one who unsealed the turtle…he's from your world, right?" Kaze asked. "Would be the only reason you'd try this."

"You aren't wrong. And this is not the first time he's done this. He's tried to control the guardian beasts of other worlds too. What he's doing goes against the laws of our worlds." Glass said.

"And trying to kill the Cardinal Heroes of other worlds is a-okay?" Nemo asked.

"Look, we can cross that bridge when we come to it." Ethox spoke up. "I mean, with the Alliance with us, I…actually don't think it'll be too hard to beat them again."

"...Yeah, that checks out." Michiru shrugged, with several others nodding in agreement.

"Entendu." Le Kraken added. "Bienvenue à bord, Vassal Heroes!"

"But don't try anything funny. If you're actually in league with whoever's behind all this and stab us in the back, you'll regret it." Ethox said.

"Okay….so…" L'Arc said as he and his party took off. "Guess we'll see who reaches him first!" he called out.

"Oh, it's like that, huh?" Akane asked.

"I guess you scared 'em, Ethox." Eddy said.

"No…He was not scared." Ethox said.

"Sadly, that is how he is." Theo said. "Come on. We need to get to that heart before they take all the glory." he said as they hurried down the tunnel.

The party continued down the tunnel and traveled to an hourglass.

"Whoa…is that its…" Cobalt asked.

"No. It's the number of souls that have been collected. The barrier is supposed to arise after the hourglass has been filled." Ost explained.

"So many…we have to do all we can to free them." Theo said as they turned back, continuing to go down numerous corridors for a long while before reaching a large chamber with a large beating heart.

"We made it. Now let's smash this thing!" Makoto said.

"Ahahahahaha!" a voice laughed in the chamber. "My my…I never expected you to come all the way here. I suppose I flirted with the idea of you showing up, but I'm surprised nonetheless."

The party got ready for battle as emerging from the darkness was a man with long white hair, glasses and a black coat.

"I suppose I should introduce myself. My name is Kyo Ethnina. And I happen to be…the holder for the Vassal Book!" he said.

"So you're the one behind the Spirit Tortoise's rampage, huh?" Hope asked.

"How dare you use a creature such as this for such needless destruction." Natyal said.

"Huh? I have no idea what that little bug is saying to me." Kyo said.

"Okay, I think we've heard enough." Mark said as he charged a Ki beam and fired it at Kyo, only for it to pass through him. "Huh? A hologram…too much of a coward to even gloat in person?"

"Wait a second… I think I've heard about this guy before." David said. "Didn't he commit suicide back in Tokyo by jumping out of a window?"

"There's lots of people who do that. Maybe he was one of them. Hard to say." Mayumi said.

"So we have the fabled Shield Hero. So you've got a mixed harem following you around." Kyo said.

"Why don't you come down here and say that, you coward?" Naofumi asked.

"My my…don't you have the high Provoke Resistance…unlike those other three losers." Kyo said.

"Other three…so we were right. You do have the other three heroes here! Where are they?" Theo demanded.

"Sorry, not telling. But I can tell you about the three who came from another world. They're currently busy slashing away at the fake hearts I set up." Kyo said as he laughed. "They really are idiots, aren't they?"

"You really do remind me of back home and not in a nice way." Naofumi said.

"As if I care. So what is it you want from me?" Kyo asked.

"We were gonna ask if you were the one behind this, but seeing the evidence, it's obvious that you are." Jexi said.

"We don't care about your origins or if you're from the same world as David or Naofumi. Surrender the tortoise's control and give back all the souls you took." DJ called out.

"Huh? Was that an order or request? You seriously need to rethink your gameplan. Did you honestly think I was going to agree to any of that?" Kyo asked.

"Look, if you wanna mess with the turtle, do it in your own damn world." Bakugo said.

"I'm doing it in this trash heap of a world cause it's so much easier!" Kyo said.

"Trust me…you were much better off doing it back in your world. Know why? Cause doing it here made an enemy out of all of us." Grantz said.

"Okay…I think I get it now…I see. Well then….best of luck." Kyo said as he suddenly vanished as a set of eyes appeared on the heart.

"He's activated the Heart's defense systems!" Vicktoriya called.

"What the hell?! What kind of Lovecraftian crap is this?!" Kazuma gawked.

"Stop gawking and take cover!" Tanya warned as the eyes started firing. Everyone evaded or blocked the eyes attacks, bombarding the area with spells.

"We need to destroy that thing, now!" Kaze said as he tossed a knife into the heart, causing Ost to wince a bit. "That's proof enough that we got the right one!"

"Sorry Ost, but we have a job to do!"

"He's right, Ost. We know how much this hurts, but this is the only way we can put it to rest. Damn that Kyo… He always was an egotistic little punk." David said. "He spent all that time in that MMO that was a hit back in the day, but one day, his account got hacked and he lost all of his progress. That must've really sent him off the deep end. Man, Connor is just the gift that keeps on giving, isn't he?"

"I don't think it's his fault this time. The events that lead to his reincarnation must have happened before the Convergence." Hope said.

"We can discuss this later! Break this heart!" Kaze spoke up as he melted into a nearby shadow, before remerging directly under the heart, stabbing it with his knives.

"Take out the eyes, the heart can't defend itself if it's blind!" Legolia said, shooting a Bomb Arrow at one of the eyes.

"Right." Tanya said as her battalion fired at each of the eyes as the sword wielding fighters went and carved right through the heart with their blades.

"Time to end this heart attack." Kaze said as his Asterisk glowed red. "Specialty: Lethal Strike." he declared as he thrusted his knife upward one final time, piercing the heart as it suddenly exploded.

Assassin Asterisk Specialty: Deadly Strike

By temporarily sacrificing all defense, the user of this Asterisk can preform a attack that deals high damage, even resulting in a one-hit kill. Defense stat will drop to 0 until the end of the battle.

"You did it, Kaze!" G. Aqua said. "We won!"

"That was a big risk… but taking down this giant reptile for good was worth it." Kaze said.

"Uh…guys? If we destroyed the Spirit Tortoise's heart, how come Ost still hasn't vanished yet?" Michiru asked, everyone noticing that Ost was still alive.

"Ost? Is…is there something…" Rishia began to ask.

"Even with its head cut off and its heart destroyed, it still lives. But…there is still more than needs to be done." Ost said as she started casting as a vast opening was revealed on the floor. As soon as it did, the group looked over as they saw the heart repairing itself.

"What in the….The Tortoise must be reviving!" Theo said.

"What's it gonna take with this thing?!" Grantz asked.

"There has to be something were missing. If cutting off its head and destroying its heart isn't the answer… then there must be a third weak point that we overlooked." Goblin Slayer said.

"Do not worry. It will all be over soon. Come." Ost said as she lead them all down the hole as it closed behind them. They ended up in a vast and sleek chamber with a large crystal sitting in its center.

"Ah…talk about a pain in the ass. And I was hoping you wouldn't show up." Kyo said as he stood above them. "But since you are…welcome to the Spirit Tortoise's deepest depths!"

"Can it, 'Book Hero'." Theo said.

"Oh…aren't we touchy? Though I'm surprised that one made it here. It must be quite a shocker to be here." Kyo said, looking at Ost.

"What's he talking about?" Raphtalia asked.

"You mean you idiots haven't pieced it together yet? Though the Shield Hero and green haired girl might have. If you haven't figured it out by now, you're an idiot." Kyo said.

"It…it can't be…" Raphtalia said.

"Yes. If you had killed that woman sooner, you could have avoided that pointless war and all those casualties. Even avoid coming in here. That woman isn't the Spirit Tortoise's familiar, she's its core! You could say she is the Spirit Tortoise itself!" Kyo said.

"You're joking…" Ragna said. "Why didn't you tell us?!"

"She probably couldn't remember." Theo said. "Though…this does change a lot of things."