The airship landed as they were deep enough inside of Sin, winding up in the strange world that made up the massive shell of armor Faust was hiding in. Unable to travel further with the vessel, they had to continue on foot, stepping down on the watery pathway. It looked like an endless sea with a bleak sky, the liquid beneath their hooves solid yet still wet.

"It's like a whole other world in here," Twilight whispered, fascinated by the inner workings of Sin.

"And I think my dad's somewhere further in...but I think we're expecting more company than him and Faust." Prepared to face the challenges ahead of them, the party walked along the long road of empty seas, Rainbow leading the group as they treaded carefully inside Sin.

There were some tough fiends that they ran across, but after dealing with Sin itself and surviving, they were no threat. All they ended up being to them were nuisances, blocking their way and tiring them out before they could reach Faust. It was as if the deity herself commanded them, though they acted on their own accord.

It took them a while to navigate the endless realm of sea, not knowing which way was a path and which way lead into an invisible wall. There were some glyphs to point out crossroads where they need to go, but they had to go around a specific way to reach them, and smacking into an invisible wall was an annoyance. After some navigating, they finally made it across, finding a stairway leading up to another portion of Sin.

As soon as they reached the top, however, all seven of them groaned in annoyance as they spotted the one pony they wished would just stay dead and get out of their lives. Standing in the center of the room, looking up at four circular glyphs with the symbols for the main elements in magic was Blueblood, the insane Guado with a sad backstory, only to have no pity after being turned into a demon as a colt. The stallion cackled, practically insane as his mane was a disheveled mess. He turned his head to face the party, his pupils shrunk to the size of pinpricks as he giggled with sickening glee.

"Welcome to my lair," Blueblood tittered, brushing his mane out of his eyes, only making his appearance worse. "See? Sin has chosen me to become its next vessel. I am a part of Sin, now. I. Am. Immortal..."

"You've lost your mind," Rainbow said. "Sin didn't choose you for anything. And you won't be Sin once we finally get rid of it."

"It is impossible. Sin will never die! Sin is eternal!" Blueblood began laughing harder, winding up on his back as he lost his balance. He managed to stand back up, glowering at them with a manic grin, his eye twitching in his insanity. "I should thank you all for stupidly killing Celestia. There will be no more Final Aeons that can stop me now! I will learn to control Sin from inside, having all the time in the world while it destroys the land! Spira will end! And I will be unstoppable!"

"You should have just stayed dead, you lunatic." Rainbow Dash pulled out her sword, flipping it in the air and catching it, pointing the aquatic blade at Blueblood. "We met your mother, who became a fayth just to give you some confidence to stand up for yourself. She showed us what you became, what you've done. When you asked for pity back in Macalania, you don't deserve any of it!"

"...So...you met my mother," Blueblood growled, his maniacal expression turning dark, glaring daggers at them. "My worthless...pathetic...aeon...My mother, who was weaker than a weak ice aeon...She is mine, and nopony else's."

"Yet you completely ignored her," Fluttershy said as she and the rest of the guardians pulled out their weapons. "She cared about you, and you're disowning her. What you turned into killed who you really were inside, Blueblood...and it hurt her to see you like this. Can't you feel her sorrow when you summon her? She's crying out for you to turn back to who you were as a colt, but you aren't listening."

"SHUT UP!" The circles behind Blueblood began to move, all of them flipping around until all of the red spheres pointed at one another. "She doesn't matter to me! She's a unicorn! I'm a Guado! SHE'S NOTHING BUT MY SLAVE THAT YOU STOLE!"

"You're not even making any sense, you idiot! Did you want your parents or did you not care about them at all!?" Rainbow asked as Blueblood hovered in the air and began transforming again.

"Nothing matters but my power! My immortality!" His body grew as he became intangible, leering down at them with soulless eyes. "I will end all your lives, and you will never stop me! NEVER!"

"...Yeah. He's too far gone. Time to send you to Tarterus where you belong!" Everyone spread out as they were about to take on Blueblood, again, and hopefully for the last time. "No more coming back from the dead!"

"I am immortal! I WILL NEVER DIE!" Blueblood's horn lit up as he cast a spell, its power multiplied by the elements pointing at him.

The party was buffeted by powerful Firaga spells, the flames far more powerful than Twilight's level of magic. They suffered through worse spells, standing back up as they were slightly scorched. Spike, using his Dragon Rage, surrounding himself and the mares with all the Nul spells and added defenses against Blueblood's magical spells. Rainbow Dash, now learning more about her hidden magical potential, increased everyone's speed with Hastega, giving them a better edge over Blueblood in agility.

"You already died!" Pinkie exclaimed as she threw up an Al Bhed Potion, healing everyone's injuries in one go. "Nopony gets a second chance at living! It's not right!"

"What's the point of living when death is inevitable for you peasants!? As long as they all know who has the most power, they will bow before anypony who saves them from an unfortunate fate!" As Blueblood was about to cast another spell, Applejack, Rainbow Dash, Spike, and Pinkie attacked the glyphs around the stallion, flipping them to different elements and ruining his magic's power. "Everypony's lives were meaningless, and even if I didn't save everypony in Luca, I would have enjoyed watching them all be ripped to shreds by our fiends!"

"What!?" Twilight gasped. "Those fiends that attacked Luca that day was your fault!?"

"I should have known," Rarity said. "That stupid grin plastered on your face said it all. A perfect ploy to garner everypony's attention to their newest and powerful maester, despite the Guado being untrustworthy before Orion tried to make peace. Know that you have just doomed your race after everything you've done to the rest of Spira!"

Rarity rushed forward and leapt up at Blueblood, slashing away at him with blinding speed, the stallion trapped in place as he was struck several times. His aura grabbed the unicorn and began to crush her, his horn glowing darker as he began to cast another spell.

"I don't care. Let the Guado rot after they denied me as one of their own. I was more a Guado than a pony, yet they saw me as a freak." Blueblood's laughter echoed as he crushed Rarity harder, making the unicorn scream out in pain. "A half-blood freak of a child, yet everypony like mother more than me...Let them die. They're no longer worth my cause. Just mere pawns! And speaking of second chances-"

Before Blueblood could finish his monologue, Spike leapt in and let out a roar, thrusting his halberd right in the Guado's eye. As he yelled in pain, his magic failed as the spell he was about to cast dissipated and dropped Rarity. The enraged dragon pulled out his weapon and pushed himself off the cringing stallion, catching the white unicorn before she hit the ground.

"You're nothing but a psychopath!" Spike shouted as he lowered Rarity down to the ground, the unicorn wincing as her body was almost crushed. "You really think killing everything will make you happy!? You killed my tribe! You're destroying your own kind! Maybe they had a right to hate you because of how you turned out!"

"...You...stupid...filthy...dragon," Blueblood growled as he held a hoof to his injured eye. "You really want to die that badly, don't you? Then why keep fighting death!?"

"Because we want to live. And if you so much as kill any of my friends, especially Rarity..." Spike stabbed his halberd into the ground, thrusting both his arms at Blueblood with his palms out. "I'll tear you to shreds!"

Blueblood was about to laugh, only to grunt in agony as he felt his life being sucked away from him. Spike's hands began glowing as he began to absorb the Guado's energy with his Lancet ability, only this time, he didn't absorb it into his own body. His scales began glowing brightly, continuing to steal more of Blueblood's life until he had taken just enough. He grabbed his diamond halberd, fueling the energy he had taken into his claws as he jumped high into the air.

At the peak of his jump, his weapon glowed brightly with power, adding more to it with his unique green flame breath. Taking aim, he threw his halberd into Blueblood, the weapon multiplying into several hundred copies as the stallion was rained down upon with magical spears. Many of them stabbed through his intangible body, sticking out from his limbs and chest as he felt his mana was being sucked out by the glowing magical spears. Spike pulled his arm back, sending them flying back to him as the halberds pulled Blueblood out of his place between the elemental circles, sent soaring in the air toward the dragon.

The halberd returned to Spike as he gained more power from the magical copies, his scales glowing brightly as the mana he absorbed began to form illusionary wings that were far bigger than Bahamut's. He let out a powerful roar as he soared down toward Blueblood, thrusting his spear straight through the Guado's chest, shattering his form and reverting him back to normal. Spike slammed the stallion hard into the ground, his weapon thrust deep in Blueblood's chest as he uttered a painful gasp, blood pooling underneath him as it leaked out of his wound and out his mouth.

"...That...was for the dragons of Mt. Gagazet." Spike's scales stopped glowing, along with his fake wings, leaving his weapon embedded in the beaten stallion. He looked over at Rarity, greatly concerned as she was almost compressed by Blueblood's telekinesis. The dragon approached her, using what little energy he stole remaining in him to ease her pain. "Are you alright, Rarity?"

"I'm fine," Rarity said. "You really are an impressive dragon, Spikey." The unicorn gave Spike a peck on the cheek, the dragon's purple face turning dark red. "A reward for my hero rescuing me."

Spike stammered as he was flattered for the "reward", quickly standing up and turning away in embarrassment. As Rarity chuckled at his reaction, the others surrounded Blueblood, the Guado staring at the fake sky inside Sin as he desperately clung to the living.

"...I-I...can't...die..." His eyes slowly looked over at Fluttershy as she held her staff close to her, ready to perform the sending to him. "...Y-You're...sending me..." Blueblood weakly chuckled as the summoner began to dance, the spirits in him flying out of him, unable to escape his fate now. "...Even if I'm gone...Spira's sorrow...will still exist...You'll...never win..."

"Just shut up and stay dead," Rainbow said as Blueblood was finally defeated and truly dead, whether his spirit was really sent to the Farplane or Tarterus was up to the afterlife's decision. As soon as the stallion's spirits finally disappeared, everypony breathed a sigh of relief. "Finally! Fighting that jerk four times is four times more than I will ever take!"

"Ya'll said it, Rainbow," Applejack agreed.

"Thank the heavens that he's finally dead! Reoccurring boss fights like him irritate the living hay out of me!" Pinkie groaned. "And his last fight was more of a pain than all of them! What is wrong with RPG developers making story-line boss fights hours before the final boss harder than they should!? It's unfair!"

"...I'm just going to take that as a grateful expression of relief that we won't ever see him again," Twilight said.

"Couldn't have translated that better myself, Twilight!" Pinkie said. "Now, on to kill Faust!...And Rainbow's dad...Oooh. That's not gonna be a good family reunion..."

"It's alright, Pinkie," Rainbow said, though a bit sadly. "I think he knew this was going to happen...Let's see what else Sin has to offer."

With Blueblood finally out of their hair, the party continued making their way through whatever other realms Sin has inside, Spike picking up his halberd where the stallion once laid. They were getting close to ending Spira's suffering, and for Rainbow Dash, the end of her and Jet Stream's lives as living dreams. The pegasus was finally going to confront her father, face to face, after ten long years. She was nervous, afraid to see him after seeing the moments where the stallion was actually sincere about her well-being, admitting he was a horrible father because he was afraid of being the terrible father he was to her. Rainbow swallowed her fears, but her body trembled lightly, terrified to hear his response if she told him how she really felt about him after all these years. She can't back down now, not when they were so close to ending Spira's pain. Next Chapter: Chapter 51: Father/Daughter Reunion/Battle Estimated time remaining: 1 Hour, 3 Minutes