"Here they come! Agh!" Sunset had no sooner called out than she was blasted by a powerful wave of sound. She fell and tumbled for several feet before stopping.
Aria swooped higher into the air and came back around, screaming another vicious spell. The pressure of the magic forced everyone but Star Swirl to their knees, and Adagio was a step behind to continue the assault.
Rainbow Dash growled and launched herself at Aria, lashing out with a fist. Star Swirl shouted a warning, but was too late to stop her. Rainbow Dash's eyes went wide as Aria effortlessly caught the attack with a single hand.
"You're kidding, right?" Aria snickered. She contemptuously pushed Rainbow Dash away, and the girl flew through the air to crash painfully into the stone side of the Wondercolt statue. Rainbow Dash collapsed to the ground.
"Rainbow Dash!" Twilight shouted, only to clutch at her head and sink back to her knees as Aria and Adagio resumed their vocal assault. She felt as if she were being shaken apart by the noise. She felt something warm and wet on her face, and realized that her nose was bleeding.
A white field shimmered into existence between the Rainbooms and the sirens, and the harmful magic stopped. Now that she had a moment to get her bearings, Twilight looked around at her friends. Most of them seemed to be okay, and Sunset had already gotten back to her feet. Rainbow Dash, however, wasn't moving. Fluttershy was already at her side, doing what she could to tend to the girl's injuries. Star Swirl stood in front of them all, one hand raised and his fingers glowing like a unicorn's horn.
He's using his fingers as a focus, Twilight realized with amazement. That shouldn't even be possible—for starters, how had he created the leylines he'd need? That wasn't even getting into the fact that, as a pony, he should be so unfamiliar with hands that they'd be all but useless for him.
Aria and Adagio had stopped their attack when Star Swirl cast his spell and simply stared, shocked, at the impossible magic. Adagio was the first to come to her senses.
"Get him!" she ordered.
Adagio opened her mouth and screamed, attempting to batter down Star Swirl's barrier with her own magic. Aria opted for a more physical approach and flew to the side, trying to get around the shield to attack him. Applejack tried to place herself between Aria and Star Swirl, but was batted aside with the same ease as Rainbow Dash.
"Twilight," Sunset urgently shook the other girl's shoulders, "we have to sing!"
Twilight shook her head. "It's no good without the others," she moaned. "We lost this fight the minute we lost our instruments."
"We have to try!" Sunset insisted. She helped Twilight up, and the two of them raised their voices in song.
Star Swirl raised his other hand and fired a ray of white light at Aria. The siren gasped and threw up her arms reflexively, and the beam broke against her forearms. Slowly, almost disbelievingly, she lowered them again and looked at the inconsequential burn that Star Swirl's attack had left.
Aria erupted into laughter. "That's it?" she choked out between chuckles. "I don't know where you got that magic from, old man, but you sure don't have enough of it."
Star Swirl fired another ray at her, his face deeply creased with concentration and sweat beginning to form on his forehead. His barrier was wavering under Adagio's onslaught. The beam stalled Aria for a moment, but she soon dove for him again with renewed confidence.
"Run," Star Swirl said grimly to the others.
"But—" Applejack started to protest.
"They're stronger than I imagined, and in this world I'm too weak to stop them," Star Swirl shouted at her. "Run!"
He was interrupted by a gleam of light from behind him. Sunset Shimmer and Twilight had managed to tap into their magic by singing and had triggered their transformations. They now stood with pony ears and tails, a thin veil of magic glimmering around them.
"I don't think so!" Aria broke away from Star Swirl and tackled the two of them, taking one with each arm. With cries of pain, the two girls fell to the ground, their magic quickly fading as they returned to human form. Aria landed heavily on top of them. She rose to her knees and lifted a fist, preparing to batter them to death, but was stopped as a rope slipped around her neck. She gave a strangled gasp as Applejack pulled the lasso tight and planted her feet, pulling with all of her considerable strength. Rarity darted over and added her own effort, and between the two of them they managed to pull Aria off of their friends.
Star Swirl gave a grunt of effort and put up his other hand, channeling all of his focus into maintaining the magic protecting them from Adagio. When the siren finally had to stop to breathe, he thrust his hands forward. A pulse of energy erupted from the shield, washing over Adagio and knocking her back several feet. Adagio recovered from the tumble and shook her head to clear it. She appeared unharmed.
Sonata hovered a dozen feet behind her sisters. She hadn't joined the battle, but was watching it with wide, tearing eyes. Her hands were clutched to her chest as if to contain the painful writhing she felt within her. What was she supposed to do?
Only one other person seemed to have noticed that there were only two sirens on the attack. Pinkie Pie was staring at her, silently begging her to intervene, to save them. Sonata could only bite her lip and shake her head. Pinkie's eyes fell, and Sonata's spirit fell with them.
Aria, unable to free herself from the rope around her neck, instead launched herself at Applejack and Rarity. Realizing that they had no chance against her head-on, the two girls dove out of the way, granting Aria the time she needed to loosen the knot and pull off Applejack's lasso. Now that she was no longer being strangled, Aria opened her mouth and let out another wave of raw sound, blasting away several of the Rainbooms.
Star Swirl sank to one knee. His barrier spell was breaking under Adagio's persistent attacks, and he had little left to put into it. As always when it came to these girls, he'd been a fool. It had been unbelievably arrogant of him to think that the meager magic available to him in this world would be enough to stop the sirens. As Adagio paused to take another breath, he sighed and lowered his hands. The weak and failing shield winked out entirely, and he instantly felt an iron grip close over his withered throat.
"Star Swirl the Bearded," Adagio purred. "I never thought I'd see you again. It's funny, isn't it? By sending us to this world, you signed your own death warrant."
"Adagio," Star Swirl croaked. "I don't know where I failed, what went wrong, but I am so sorry that it's come to this."
Whether because he'd reached her or simply out of surprise, Adagio's hand relaxed slightly. "What are you talking about?" she asked.
"Don't you remember me?" Star Swirl asked.
"Of course I do," Adagio growled. "You're the one who banished us to this awful place over a thousand years ago."
Star Swirl shook his head. "Is that all I am to you?" he asked sadly. "You mean so much more to me." He bowed his head, ready to accept his fate.
"What are you waiting for, Adagio?" Aria demanded. "Do it."
"Hold on, this geezer's got me curious," Adagio answered. She crouched down to look Star Swirl in the eye. "Exactly what do we mean to you, old man?"
"No more mistakes, remember?" Aria shouted. "Kill him before something else goes wrong!"
"Star Swirl's the one who created you!" Twilight blurted out.
Everything seemed to stop. Adagio's grip on Star Swirl's throat loosened, then she let go entirely. She stood up and took a shaky step backward. This wretched old stallion was the one who'd given them life?
"Something like that," Aria said quietly. She looked to Adagio, who simply stared back at her. Both directed their gaze to the ancient man kneeling before them, the very picture of penitence.
"It's true," Star Swirl murmured. "Adagio Dazzle. Aria Blaze. Sonata Dusk. I may have created you with magic, but that doesn't make you any less my daughters. And I have been a poor father indeed." He looked up at them beseechingly. "Please, come back to Equestria with me. I should never have sent you away. Whatever went wrong between us, we can fix it. I beg you, let's start over."
Adagio and Aria stared at one another in silence, processing this new information. This last shock had proven too much for Sonata, who now knelt weeping with her hands over her face. The Rainbooms and Star Swirl waited with bated breath to hear the sirens' decision.
Star Swirl gasped as Aria's hand closed around his neck. She'd moved too quickly to follow, and now she hoisted Star Swirl off the ground with a single hand.
"Even if that is true," Aria said, "it doesn't change anything. Too little too late, 'Dad.'" She tossed him to the ground next to the others. Only Pinkie Pie remained on her feet, and she seemed to have lost the will to fight.
"Adagio?" Aria prompted her sister.
"Right." Adagio rose into the air with Aria beside her. "I think I'll call this one the Rainbow Requiem. Goodbye, Rainbooms." For some reason, the sweet words tasted like ashes in her mouth.
Adagio and Aria opened their mouths and began to sing. Their hearts glowed brightly, and magic gathered around them. It was a deadly spell, one that would strike to its victims' very cores, destroying them from the inside out. This was something they hadn't had to do in many centuries, but the power still came to them with ease. Their eyes shone red as the power peaked, and they unleashed it toward Star Swirl and the Rainbooms. It was over.
Their deafening magic met unexpected opposition.
"What?!" Aria shouted as the waves of energy tangled up with something else. Someone was standing in the way of their spell, countering it with magic of her own. With a final burst of discordant noise, the killing spell broke apart and dissipated, revealing the Rainbooms' savior.
"Sonata," Adagio growled.
"Don't do this," Sonata begged them. Tears streamed from her closed eyes, but she stood her ground. "Please don't hurt them anymore."
"What in Tartarus do you think you're doing?" Aria demanded furiously.
"I'm saving them," Sonata said softly. "They fought so hard to save me, to save us all. Now I'm going to save them."
"You can't." Adagio planted her hands on her hips. "You can' t beat us both."
Sonata shook her head. "You're wrong," she whispered. "Right now I have more energy than both of you put together. Please... please don't make me do this."
"Sonie," Pinkie Pie murmured, her own eyes beginning to tear up.
"How..." Aria gasped as she realized what must have happened. "The dark magic!" she exclaimed. "That's why these brats are still alive. You absorbed it all, didn't you?!"
Sonata simply nodded.
"You bitch!" Aria raged. She hurled herself forward and, before anyone could stop her, struck Sonata full across the face. The blow would have snapped a human's neck, but Sonata barely turned her head as it landed.
"Hey!" Pinkie leaped forward to help, but stopped as Sonata held up a hand.
"It's okay," Sonata said. She didn't acknowledge the swelling that was beginning to form on her cheek, or the stinging as her warm tears washed over it. Aria threw another punch, but Sonata caught it and held her sister by the wrist.
"Please," she said to Aria and Adagio, "just stop this. We don't need to live like this anymore."
"What else would we do?" Adagio demanded.
"I don't know," Sonata admitted, "but I do know that what we're doing now isn't going to make us happy. It's never made us happy."
"That again?" Aria scoffed.
"You know what made me happy?" Sonata continued as if Aria hadn't spoken. "Spending time with you two. Hanging out with these girls." She pointed behind her to the Rainbooms. "When they all worked so hard to help us for no reason other than because it was the right thing to do, that made me happy. When Pinkie gave me her phone number, and treated me like her friend, and hugged me, that all made me so happy. Yesterday meant more to me than the last thousand years put together. Please, I just know there's a better way."
"Touching," Adagio droned. Why were her eyes burning? "Are you finished?"
"Sonata's right," Sunset spoke up from where she lay. She pushed herself up to her elbows. "This was something I had to come to terms with after the Fall Formal. All that time I had thought I wanted power, but power's just a means to an end. It isn't and will never be an end in itself, and that's why you'll never be satisfied no matter how much you gather. In chasing something that didn't matter, I pushed away everyone and everything that did." She closed her eyes. "It took Twilight and her friends to show me that."
"I know you're not as cold as you pretend to be, Adagio," Sonata persisted. "Do you think I don't know that you were feeding Aria with your own magic for all that time after our hearts broke? Do you think I didn't hear you both crying at night? I know you were as sad and scared as I was. I know the two of you aren't heartless."
"We can use metamagic to find other ways for you to feed," Twilight suggested. "You don't need to keep hurting people. We might be able to alter your hearts, or even just give you arrays, so that you can eat regular magic or harmonic magic. You can spread friendship and happiness instead of jealousy and anger."
"Hmph," Aria grunted. "That's great and all, but—" she shoved Sonata away with all her strength and flew into the air—"we've known about metamagic for centuries. Did it ever occur to you that we do things this way just because we enjoy it?" She took a deep breath and opened her mouth to sing.
Sonata blurred forward and closed her hand around Aria's pendant. The first notes of Aria's song cut off with a gasp.
"What are you doing?" Aria asked. For the first time, she sounded truly afraid.
"I'm sorry, Aria," Sonata sobbed. "I love you."
Her hand glowed green, and she forcibly took the magic from Aria's heart into herself. Then, with a sharp jerk, she pulled the pendant away from her sister's neck.
Aria's wings and ears winked out of existence. Adagio shouted in alarm and flew forward, catching her as she fell. Cradling the fallen siren, Adagio glared up at Sonata with her teeth clenched and eyes watering.
"So this is it, then? Traitor."
"Please, this isn't what I wanted," Sonata wept.
"Then what did you want?" Adagio demanded.
"I just wanted everyone to be happy. I wanted us all to be friends. I'm sorry," Sonata repeated, clutching Aria's heart to herself.
"You will be." Adagio's eyes glowed red. She laid Aria gently on the ground and rocketed up toward her other sister, hands extended like claws.
Sonata batted aside the first of Adagio's attacks and slipped inside her guard. She lifted her own arms and caught the enraged siren in a loving embrace. Sonata began singing gently, for Adagio's ears only, a quiet lullaby of comfort and peace.
"Let me go!" Adagio demanded. Her voice croaked strangely as she felt her throat tightening. Despite her angry words, she only struggled for a moment. "Let me... go..."
"No," Sonata whispered over the fading echoes of her song. "It's over. You felt it too, didn't you? You know that what we're doing is wrong."
Almost of their own accord, Adagio's arms rose and wrapped around Sonata. The furious red light faded from her eyes, leaving them looking scared and lost.
As Adagio let go of her magic, the mob around them stopped what they were doing and looked around, confused, wondering why they'd felt so angry. There were many explanations and apologies between the people, and the crowd dispersed largely of its own accord. Teachers and administrators, also freed from the sirens' magic, worked quickly to get the students back inside and away from what could still be a dangerous situation.
"What will we do?" Adagio asked, resting her head against Sonata's shoulder.
"I don't know," Sonata murmured.
"What about Aria?" Adagio choked.
"She'll be weak for a while, but she'll be okay."
"That's not what I meant." Adagio shook her head. "She'll never accept living the way you want us to. I'm not even sure if I can." In spite of what she said, it didn't actually sound so bad. They had enough money to live well for decades to come, and having people actually like her, rather than be enchanted to adore her, sounded surprisingly nice.
"We'll figure it out," Sonata said. "You always come up with something." She gently tapped Adagio's nose with a finger. "You're the smart one, remember?"
Adagio gave a low chuckle. "I am, aren't I? Just this once, you might be right." Who could have imagined that Sonata would end up being the strongest and best of them?
The two sisters descended from the sky and landed next to Aria, who was now recovering from the shock of having her magic torn away again. Aria sat up and held a hand to her head. She looked around at the Rainbooms, who were climbing one by one to their feet, and the sirens who were doing nothing to stop them. She opened her mouth angrily, then closed it as she realized that she was beaten. Again.
"That's it, then?" Aria asked, looking at Sonata and Adagio. "This is how it ends for us?"
"No," Adagio replied. "I think this is how it begins. So, Rainbooms," she said to the others, regaining a hint of her usual swagger, "what now?"
Twilight looked around at her friends: Sunset Shimmer, who stood beside her with a determined set to her jaw. Fluttershy, who was helping a still-woozy Rainbow Dash to stand. Rarity and Applejack, who were looking on in concern. Pinkie Pie, who was staring at Sonata and smiling even as tears streamed down her cheeks. Star Swirl, who was beaming proudly at his daughters. For a miracle, everyone was alright.
"I'll need the three of you to come back to Equestria with me," Twilight said. "I'll take you to Canterlot and we'll talk this over with the other princesses. I'm sure we can reach an agreement that works for everypony."
The sirens looked at one another, and Twilight experienced a moment of panic as she thought they might refuse. To her relief, Adagio and Sonata finally nodded.
"Sonata?" Twilight said hesitantly. This was still a very delicate situation, and she realized only too well that she could still lose control of it.
"Hm?"
"I'm going to need to hold onto Aria's heart, just for now," Twilight said. "I can't take any chances. She'll get it back as soon as we talk with Celestia and Luna."
Aria looked like she was about to protest, but instead she just huffed and turned away. "Whatever."
Sonata hesitantly approached Twilight and held out Aria's pendant. Twilight carefully took it from her hand and put it into her backpack. "I won't let anything happen to this," she promised.
"Here," Sonata said, removing her own heart and holding it out for Twilight.
"Sonata, that's not—"
"I did all the same bad stuff that she did," Sonata said. "If you're taking her heart, you're taking mine too."
Twilight hesitated to voice her actual concern, which was that Adagio could still attack. Sonata wouldn't be able to stop her without her heart. Star Swirl, however, seemed to realize the issue. He slowly approached the other siren.
"Adagio," he said, gesturing to her pendant. "May I?"
"No," Adagio said curtly. "Don't think you can just waltz into our lives after a millennium and expect everything to be alright. She can hold it." Adagio nodded to Twilight.
"Of course," Star Swirl replied sadly. Adagio pushed past him and walked to Twilight to hand over her pendant.
Twilight breathed a silent sigh of relief as she took the third and last of the sirens' hearts. It was really over.
"You're going back to Equestria, then?" Rarity asked quietly. "Would you like us to go with you?"
Twilight really wanted to say yes. She wanted nothing more than to have her friends' support in this, but...
"Better not," she answered. "This is going to be complicated enough without having to explain about you girls."
"What about me?" Sunset stepped forward. "I could go with you."
Twilight thought it over and smiled. "I think that's a great idea," she said. "And Star Swirl will have to come too, of course."
"So be it, then," Rarity sighed. "You will come back and tell us how it all goes, won't you? We must have a proper visit sometime soon."
"Of course I will," Twilight answered. "I'll see you all soon, okay?" She gathered up Sunset, Star Swirl, and the sirens, before realizing that there was one last problem to deal with.
"Sonie?" Pinkie said, her voice trembling. "Are... are you coming back?"
"I don't know, Pinkie," Sonata answered sadly. "I hope so, but that's gonna be up to the princesses."
"But, but, but you're good now!" Pinkie cried desperately, clinging onto the siren. "They have to let you come back!"
"I think they'll be alright," Twilight reassured the others. "There's quite a lot of precedent for this kind of thing: Princess Luna, Discord, even Sunset Shimmer. I'd be really surprised if they aren't granted a pardon in exchange for agreeing to use their powers for good."
"You promise?" Pinkie asked. She still sounded terrified, and hadn't let go of Sonata.
"Pinkie promise," Twilight answered.
"C'mon, Sugarcube," Applejack said, gently prying her away from Sonata. "Twi's got princess stuff to do. The sooner she does it, the sooner we can all go back to bein' friends."
"Fluttershy," Adagio said unexpectedly.
"Hm? Uh, yes?" Fluttershy stammered.
"Thanks for hanging out with me yesterday. I... had fun."
Fluttershy nodded. "Anytime."
"Everyone ready?" Twilight asked. They all nodded. "Then let's go. Back to Equestria, one more time." She squeaked in surprise as she was caught in a huge group hug.
"See ya soon, Twi, Sunset," Applejack said.
"We'll be waiting," Rarity promised.
"Later, alligators!" Pinkie chirped, recovering much of her usual cheer.
"Have a nice tuna," Rainbow Dash slurred.
"Oh dear," Fluttershy murmured. She held up a finger and was relieved to see that Rainbow's eyes were able to follow it. "Don't worry, she's just a bit disoriented. She'll be just fine by the time you get back."
"Which will be soon," Twilight promised. "See you girls later."
With much waving and hugging, and a few tears, Twilight finally led the sirens back into Equestria.