"Battle perimeters met! Summoning Yo-kai!" Twilight took the six medals out of her Yo-kai Medallium and smashed them into the slots on her Yo-kai Watch EX. The lights danced in the sky as the Yo-kai landed on the cruise ship. "Yo-kai fighters, roll call!"

"Sgt. Burly!"

"Gargaros!"

"Moskevil!"

"Houzzat!"

"Impass!"

"Count Cavity!"

"No healers this time?" Whisper looked at Twilight's new Yo-kai team. "Don't you think that you're playing a dangerous game by doing that?"

"Whisper. We just beat an SS Rank Yo-kai with nothing more than Mermaidyns, and a Mermother and Mermadonna." Twilight saw the mermaids battle against the water. "If they can manage Maelstro's waters, then they can help us in fighting her."

"Aqua Grasp!" Maelstro swung her baton, causing water to spout up and smash against the ship, pulling Sgt. Burly, Gargaros, and Impass into the maelstrom. She tried to grab the other Yo-kai as well, but they simply flew out of her grasp and slashed the water away. "Ah. A captive audience for my marvellous music. That's how a musician should flourish, isn't it?"

"What the heck are you?" Applejack asked as she pulled her head from the raging waters. "And why do ya'll want Midnight Sparkle? Ain't it easier just to kill Twilight and be done with it?"

"If only it were that simple, little country girl." Maelstro leaned over to Applejack and manipulated the water to pull her close to her face. "But I'm afraid that you can't just kill off the heroes all willy-nilly. It'd ruin the atmosphere and the challenge of King Void's conquest." She flashed an innocent grin at the rest of the girls. "What's the point of conquering the world if you don't have someone trying to stop you? Isn't that how heroes and villains work these days?"

"She does have a point." Pinkie raised her finger. "The whole reason we have big meanie-pants villains like King Void, Lord Tirek, and Queen Chrysalis is because we're the good guys. We're never not going to see a villain because we're the heroines. And similarly for them, they won't ever be able to take over the world because we're saving it. It's kind of a weird cycle, really."

"Exactly, pink-haired mermaid." Maelstro smiled and threw Applejack back. "But at the same time, the heroes don't get to save the world without a challenge either." She chuckled and put her hand to her mouth, turning towards her podium. "And now, Maelstro, if you please? Oh, thank you, me. No, thank you. Aw, you're a real doll, aren't ya?"

Maelstro tapped her baton against a podium with musical score on top of it. She raised it high to her instruments, and with a powerful swing, loud notes blasted out of the instruments and flew directly towards Twilight and her team of Yo-kai. Brass, wind, drums, string, and a whole slew of other musical instruments all floated and danced in the air as Maelstro conducted each and every one of them.

"Team! Try to survive agai—" before Twilight could finish, the water sucked her under.

"Twili—" Rainbow Dash was smashed with water and pulled under as well.

"The power of the ocean compels you all!" Maelstro called out to everyone in the whirlpool. "Let it drag you under and consume your souls! Let the very water wrap itself around you and drag you all down to your swamped graves!"

As Twilight and her Yo-kai fell under the water, they saw that a large fan was on the undercarriage of Maelstro's platform. It was generating a massive tornado that bored into the ground and sucked in everything around it—including the Mermaidyn kingdom and any nearby life forms around it.

Twilight's ground-based Yo-kai were swimming up to the surface, only to be pulled back down again as the waters got even more violent. Whenever they were under the water, they had to hold their breath for elongated periods of time as they desperately thrashed and swam against the roaring torrents to get back to the surface.

"This is bad." Twilight swam backwards to avoid being sucked into the tornado. "If we don't beat Maelstro soon, she's going to take the lives of hundreds of innocent ponies!" She shot herself up out of the water and fired spells from her horn at Maelstro's instruments.

"You look like you could use some help." Count Cavity swooped down and jabbed at the incoming musical notes. Once he had skewered enough, he shot them back at Maelstro, throwing her against the podium.

"Hey! No interrupting the performance!" Maelstro swung her baton at Twilight and her Yo-kai. "Crescendo of Chaos!"

More and more musical notes were fired from the instruments. They danced around the ponies and Yo-kai before crashing directly into them, exploding on impact. It was enough to knock the flying Yo-kai out of the sky and into the waters.

Maelstro jabbed her stick out like a fencing sword, causing the wing instruments to point themselves directly at the girls. With a loud blast, ten massive black lasers shot and pierced the water momentarily, grazing against Twilight and her team of Yo-kai.

"C'mon, everyone!" Burly shook off the pain and swam against the raging waters. "A little bit of swimming never hurt anyone! Swing those arms, fingers pointed forward! Face that water like it's your worst enem—"

"SILENCE!" Maelstro leapt up and pointed her baton at Sgt. Burly, causing the instruments flying around her to point themselves at the swimming Yo-kai before opening fire. All of the notes hit Sgt. Burly on the head, disorienting him and pushing him under the water. "There is to be no talking during my performance!"

"Your performance?!" Twilight pulled Sgt. Burly out of the water and used her magic to lift Impass and Gargaros out as well. She levitated all three of them over to the platform and moved to help out her flying Yo-kai. "You're not even allowed to be here! Get out of here before you hurt someone!"

"That's the point!" Maelstro swung her baton in a circular motion, causing a spiral of water around Twilight to gush up and throw her into the air. "Aqua Grasp!" She grabbed Twilight with the water and pulled her towards the platform. Once the pony was in range, she dealt a strong and fast kick to her, sending her back into the vortex of ocean.

"Twilight!" Mermother called out and hurriedly swam over to her, propelled through the sea by the speeds of the maelstrom.

Twilight was back in the black space where she had first met Midnight Sparkle. Only this time, she could hear the sound that she was underwater. Bubbles flew up past her face in a thin tower-like pattern. She was still a mermaid, but she felt completely dry when she brought her hands to her chest.

"Oh no. Not again..." Twilight looked around to try and find her friends in the darkness. Just like before, she found absolutely nothing but darkness.

"Oh yes again." Midnight materialised behind her and sensually slid her claw down Twilight's cheek. "Hello, Twilight. Have you accepted the darkness within you yet?"

"Midnight!" Twilight jumped at the sight of Midnight and readied her horn for a spell. She fired it at the demonic creature but watched it faze straight through her. "Just leave me alone! You can't control me!"

"Oh, but I think you'll find that I can." Midnight chuckled and flew over to Twilight, grabbing her by the cheeks and pinching them gently. "Poor widdle Twilight Sparkle. She thinks that she can destroy me and save the world. Isn't that just precious?"

"Yes. Such a weak-minded child can't possibly hope to comprehend how easy it is to let the darkness slip out." Maelstro appeared in a dark purple blast before Twilight and Midnight. "It's no wonder that she struggles against the Dark Yo-kai."

"Ah! You must be my brand new friend." Midnight Sparkle gave a gentle grin to Maelstro. "See, Twilight? She embraces the darkness, so why can't you? Don't you want to stop King Void and save your world?"

"Stop it! Stop trying to fill my head with lies!" Twilight fired bolt after bolt of magic at both Maelstro and Midnight, who both dodged them with little effort. "You're just nightmares! Ones that I can easily get rid of!"

"But, see, there's the problem, Twilight." Midnight flew back over and glared into Twilight's eyes, casting a sadistic smile on her. "I. Am. You!" She licked her lips and whispered into her ears, "Anything you think you can accomplish, you can't. I am you. I will always be you. You simply have to hate your friends, take revenge on them, make them hate you in return! Only then will you liberate yourself from this weak little thing known as the Magic of Friendship."

"What you call darkness is merely your failure to see the possibilities of what lies beyond light." Maelstro swam up to Twilight and coiled her arm around the pony's body. "Give in to that darkness, destroy me, and prove that you are an evil little pony who doesn't deserve friendship."

"Give in, Twilight. Give in to us. Give into your hatred. Give in to the darkness!" Midnight jumped onto Twilight's back and strapped herself on tight.

"Give in! Give in! Give in!" Both Midnight and Maelstro began to chant, throwing down their arms as they did.

As Maelstro and Midnight chanted, darkness began to swirl up around the three of them. It slowly but surely enveloped all three of them from the feet upward. While the two of them smiled at the sight of being devoured by the darkness, Twilight simply gasped and tried desperately to fly away.

"No! NO!" Twilight cried as she darted towards the surface, tears streaming out of her eyes as she tried to get away from the darkness, which now had four purple eyes glaring at her as she fled from it. "I'm not a monster! I'm not evil! And I'm not darkness!" She didn't even see the darkness consume every part of her body. The cyan masked appeared around her face and she threw her limbs out to the side as raven-black wings appeared on her back. "I'M NOT A VILLAIN!"

"Twilight!" Mermother finally caught up with Twilight and wrapped her arms around her, barely staying away from the raging tornado underneath Maelstro's platform. "C'mon! Wake up! You're stronger than this."

"Yes." Twilight's eyes shot open, as Midnight's mask and horn appeared on her face, with the black wings sprouting on her back shortly after. "I'm so strong that I'll destroy everyone! I'll kill you, your pathetic friends, and everyone who gets in my way, starting with Maelstro up there!" She cackled and flew up out of the water, leaving Mermother to the fan at the bottom of the platform.

"Has anypony seen Twilight?" Applejack asked as she pulled her head from the water, seeing that the cruise ship was beginning to break apart. "These ponies are about to die!"

"I'm trying, Applejack! Don't make me even more pressured!" Rainbow Dash swam under the water and back up again repeatedly to try and find Twilight. "Y'know, I think we should actually try and attack Maelstro instead of worry about Twilight! She's a strong pony! She'll make it through this!"

"Uh, girls?" Pinkie Pie looked under the water again. "When did Twilight get those raven wings of hers?"

"Raven wings?!" Rarity gasped and watched Twilight shoot out of the water and fly over them all. "Oh no! It can't be!"

"But it is..." Fluttershy whimpered and swam over to Rainbow Dash. "Please look after me, Rainbow Dash. Midnight Sparkle's back..."

"I'm back!" Midnight cackled at the group of ponies. "Did you all miss me? I'm sure you did."

"Midnight Sparkle." Maelstro stopped the music and conjured water to make stairs. She then proceeded to walk up those stairs to meet the cyan-masked demon. "King Void requests an audience with you. Come with me and I'll bring you right to him."

"If I'm going to meet King Void, he's going to have to come and meet me himself—not send his flunkies to deal with the messages." Midnight scoffed and crossed her arms, looking down at the group of ponies on the cruise ship. She coiled her fingers and fired a massive laser, splitting the ship into pieces and sending all of the ponies into the water. "They were going to die anyway. Thought I'd speed up the process." She turned back to Maelstro. "But anyway, I'd rather that the king come down here and show his ugly mug to me personally."

"I wish I could bring him down, but he's busy trying to find Kin and Gin." Maelstro shook her head. "You know, ever since Dame Dedtime was defeated, those two always keep running away on their own devices. Wish they could just learn to sit still for once in their afterlives."

"I don't care about two elderly freaks who aren't using their two power." Midnight shook her head and fired more bolts down at the ponies in the water, turning them into dust that scattered and sank underneath it. "If King Void wanted me to join him, he would've come down to say so. He doesn't really sound like much of a ruler to me."

"Shut your face. King Void is the most powerful Yo-kai of all!" Maelstro jabbed a finger at Midnight. "He was born from all of the darkness of every Yo-kai in existence—even the evil of Lord Enma himself. So it's safe to say that he is a quadruple S-Rank Yo-kai. Untameable, unbeatable, and one who will conquer these miserable worlds."

"If anyone's going to rule this world, it's going to be me." Midnight conjured purple orbs around herself and barraged Maelstro with them, smashing her against the platform. "Midnight Sparkle doesn't need a king! She doesn't need anyone! All that she needs is destruction, death, and the joy of hearing those little ponies scream their last breaths as their bodies are reduced to ashes!"

"Arrogant little piece of..." Maelstro muttered and took in black energy. "Dark Soultimate Charge!"

Mermother, Mermadonna, and all of the Mermaidyns looked out at Maelstro and Midnight, swimming away from the platform as they saw the Dark Yo-kai gathering energy for a Soultimate. They all watched on with frowns and gasps as the sky turned purple, with thunderbolts crashing down on the seas beyond.

"Time to die!" Maelstro stomped on her platform and coated her baton in black energy. She swung it as if she was painting a japanese symbol, causing the music from the instruments to intensift. "ENDGAME ENSEMB—"

"OCTO SNAKE!"

"INFERNO!"

A massive fireball engulfed Maelstro as she was about to thrust her stick forward, while hundreds of teal dragons began biting into Midnight Sparkle. Both targets jittered and jolted around in the attacks as Venoct and Kyubi both kicked them square in their eyes, knocking them both out and into the water's depths.

The water instantly returned to normal once Maelstro was smashed against the platform, and the sky cleared up and turned back to blue once again. Midnight Sparkle let out a small breath before she turned back into Twilight Sparkle. Before she could hit the water, Venoct swooped down and picked her up, cradling her as she struggled to breathe.

"Im...possible." Maelstro tried to stand up, but Kyubi stomped on her chest, causing dark purple matter to spill out of her mouth, similar in colour to how the Dark Yo-kai looked. "How cou—"

"Save your breath, Dark Yo-kai." Kyubi got into Maelstro's face and grabbed her by the neck. "You're going to need it when Queen Ephemer interrogates you later." She took the baton and snapped it clean in half, throwing it far away from her pinned-down victim. "There. No more mayhem."

"You... vile... Kyubi!" Maelstro began to wrap her hands around the nine-tailed fox, trying to get her off of her body.

"Ugh. What a crybaby." Kyubi scoffed and pulled both of Maelstro's arms off her neck without any effort. "Honestly, even Dame Dedtime and the Wicked knew when they were beaten." She disappeared in smoke, taking Maelstro with her.

Venoct put Twilight down on the deactivated platform, using Orochi to destroy what remained of Maelstro's instruments. With fierce snaps and lunges from his dragon scarf, the entire set was destroyed, leaving the platform entirely barren.

"Is she going to be alright?" Fluttershy gently paddled up to the slumbering Twilight, with the rest of her friends close behind her.

"She will be." Venoct put his hand on Twilight's chest, feeling it move as she breathed very lightly. "Just give her some time to recover. Seems being Midnight really took its' toll on her this time..."

The other Main Six swam up and saw the state that Twilight was in. Her hair was frazzled and she couldn't even open her eyes. The mask and horn had vanished and she was still in her transmogrified state from when they had first met Mermaidyn, but she was still unable to open her eyes or even speak with how lifeless she seemed.

Author's Notes:

Just so you know, I have seen more of the anime and heard Venoct's dubbed voice. And let me say, that in comparison to his medallium entry from the games and from his real-life Yo-kai Medal, he sounds absolutely perfect in the anime. His deep and brooding voice matches perfectly with his personality, and I really did enjoy seeing him throw down with Rubeus J.

Also, there will be a stats page on Mermonster and Maelstro to come shortly, so be sure to check that out when it comes. And if you did enjoy this arc, then be sure to leave your comments down below on your thoughts about it.

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