In town the girls finally reach the old opera house as Sonata leads the way. “Right through here. We have to be quiet.” She leads them around the back entry way where she removes an old wooden plank, revealing a hole in the wall. “Follow me.” The group sneak inside and follow Sonata as she leads them through the halls to the back stage. As they make their way they can hear Adagio speaking to someone. Everyone takes up a hiding place as the two converse.
“Alright, now that I have Sombra's power and he's out of the way for good let's get going.” Adagio says as she stumbles, falling on one knee.
“Are you okay?” Lightning Dust asks as she helps her to her feet.
“I'm fine. I've never absorbed so much power at once before, that's all. Once we're back in Equestria we'll destroy the portal. With Twilight Sparkle trapped here there will be one less princess to stand in our way and I can finally put this place behind me.”
“Adagio?” Sonata says walking out onto the stage. Sunset and the others are shocked as they look over to where she was hiding. Sunset takes the opportunity to head back down the hall where she spots a stairwell leading up to one of the balconies. Adagio's right eye begins to twitch as she turns to see the younger siren.
“You want me to take care of this my queen?” Dust asks only for Adagio to stop her, gesturing the girl to back away.
“You shouldn't be here Sonata.”
“I don't understand. Why are you doing this Adagio?”
The elder siren begins to chuckle. “You bubble headed dimwit. You really don't get it do you? Let me spell it out for you. I lied and tricked you to get the portal open. Now that I have Sombra's magic what do I need from you?” She holds out her hand toward Sonata, who begins to levitate.
“That's it, I'm not waiting around anymore.” Rainbow Dash rushes out as the others, with no other option join her. “Let her go!”
Adagio looks over at the group with slight annoyance. “You want her? Fine.” She hurls Sonata through the air, sending her crashing into Pinkie and Applejack. Sonata looks back toward her sister with tears in her eyes. “All I've ever wanted was power and it's never been enough. Now I have the chance to gain more power than I could have ever dreamed of and this time I won't have to share it with a hot-head like Aria or a ditzy fool like you. So now I'm headed back to Equestria where I'll be unstoppable.”
“Not if we have anything to say about it.” Twilight says as the others rally around her as they begin to channel their elemental powers. They unleash their power as the blast approaches Adagio, with Lightning Dust leaping off the stage to safety.
“Oh don't worry. You don't.” Adagio sings her siren song, effectively shielding her from the attack. This leaves the girls stunned as the siren is likewise impressed by her new abilities. “Now that's the kind of power I'm talking about.” She sings her song once again, sending a wave of energy that knocks the girls to the ground as she begins to float high above the stage. “And that was only a fraction of what's in store.”
“Come on. Don't give up. We can do this.” Twilight says as the girls get back to their feet. Adagio prepares to attack again as Sonata stands between them.
“Get out of the way Sonata.” Adagio says.
“Yeah Sonata, move.” Dash yells to her.
“No. I'm not going to let you hurt my friends. I...I don't want to fight you Adagio.” She stands defiantly as Sunset makes her way to the balcony above Adagio.
“Oh stupid little Sonata. You never were too bright were you?” Sonata's eyes begin to tear up as Adagio continues her verbal assault. “No wonder they said you were the cute one. It made up for the lack of any brains in that empty void you call a head. But by all means, give me your best shot.”
Sonata falls to her knees, recalling all the insults she suffered over the years. She manages to drown these thoughts out with the good times she's had with Pinkie Pie and the others. Getting back to her feet, Sonata begins to sing her song as well, with her sister looking on, visually unimpressed. The blue haired girl sends out her own wave of sound that forces Adagio backwards, much to her and the others surprise. Seeing the siren temporarily weakened, Sunset makes her move, leaping off the balcony as Adagio turns to her. They collide in mid-air as they wrestle for control of the gem. Amidst the scuffle Sunset's hand connects with the stone and her eyes begin to glow just before the two crash to the ground. Adagio crawls away, clutching her shoulder, leaving the unconscious girl.
“Sunset Shimmer!” Twilight shouts as she and the other girls rush over to help.
Lightning Dust rushes to the stage helping Adagio as she turns back to see Sonata attempting to approach her. “Get away from me!” She shouts in a panic, confused as to how her sister was able to cause her pain. “Just stay away from me!” Sonata stops as Adagio backs away from her, seemingly in fear. She sings a song with such concussive force that it begins to crumble the walls of the building.
“Have fun fishing for your friends in the rubble.” Lightning Dust jokes as she helps Adagio to escape. Meanwhile Rainbow Dash and Applejack lift up a still dazed Sunset. “Adagio, wait!” Sonata cries out as a large chunk of the ceiling obscures her view of her sister.
“We need to leave now.” Rarity shouts as they head back toward the exit, the building becoming more and more unstable as they rush back. They quickly file out and make it back across the street as the opera house finally comes down. The group continue to run until they are a few blocks away. They carefully lay Sunset on a bench as she slowly comes to. “We have to keep them from reaching the portal. Who knows what kind of damage they could do if they get through?” Twilight says as the others think of what to do.
“What can we do. We couldn't even touch her.” Applejack admits.
“But you could Sonata.” Fluttershy says as the siren looks over.
“I couldn't let her hurt you girls. Even if she is my sister, I can't let her do this.” She says with a new found determination in her eyes.
“That's it. Friendship must have given your song the power to generate positive energy instead of absorbing the negative. That must be how you were able to nullify her attack.” Twilight explains.
“Looks like we have our own secret weapon.” Rainbow Dash says. “Pinkie Pie, Rarity, stay here with Sunset. The rest of us we'll catch up to them. Let's go.”
Canterlot High
Having successfully escaped he building, Adagio and Lightning Dust make it back to the school. In front of the portal they find Aria with Snips and Snails standing between them and their goal. “Where do you think you're going?”
Adagio finds herself chuckling. “And here I thought Sonata was the dumb one. I'm going through that portal and you're going to get out of the way.”
“Why are you doing this Adagio. What about all the stuff you said about wanting to make things right?” She finds herself being lifted off the ground by Adagio's new powers.
“Well that was then, this is now. And now, I'm the most powerful being on this planet and soon all of Equestria.” Snips and Snails, despite being completely terrified rush to help her, only for Lightning Dust to stand in the way.
“You boys want to wrestle, huh? Well come on then.” She rushes the two, tackling them as Adagio has her sister at her mercy.
“I can't let you do this Adagio.”
“Oh and what are you going to do, beat me up? Oh I forgot you don't do that anymore. You're as soft as a baby bunny now. So pathetic. Your so called friendship hasn't done you any favors has it now?” She turns her attention to Aria's lackeys who are already subdued by Dust, levitating them with her powers.
“Leave them alone!” Aria struggles to get free.
“Come on Aria, get mad, do something about it. The old Aria would.” She taunts as she sees her sister getting angry before she closes her eyes, tears running down her face. “That's what I thought.” Adagio screams out, dropping all three as she loses her concentration. She looks down to see Spike biting her left leg. “Get off!” She kicks him off as he tumbles, landing near Aria who is still on the ground.
“Thanks Spike.”
“No problem.” He looks up to see Adagio standing over them. “But this is.” He covers his eyes as she and Lightning Dust see the others coming and make a break for the portal.
“Adagio please don't. It's not too late to stop this. Just find the light inside of you.” Aria pleads as her sister stops inches from the portal.
“There is no light inside me.” She swiftly disappears through the portal as Dust follows closely behind.
“Aria, are you alright? What happened?” Fluttershy rushes over to help her up.
“I thought we could stop her. Snips, Snails, I'm sorry for putting you in danger like that.”
“Don't sweat it, this is nothing compared to last time. Right Snails?”
“Yeah I'd do anything for you.” Snails says with a lovestruck smiles as Aria turns her attention back to the portal.
“I can't believe I didn't stop her. She was right in front of me and I didn't do anything. She was right, I'm pathetic.” She looks up as Sonata puts a hand on her shoulder. “Sonata, I'm so sorry for what I did. I should have told you what Adagio was planning. I just thought she would change.”
“And I'm sorry too. I should have believed you. And don't listen to Adagio. You're stronger than before, just like me. You use your strength to defend others instead of bullying them, like you helped out Snips and Snails. Now we need to help defend Equestria from our sister.”
“I can't, all I'll do is mess everything up.”
“Take it from someone who's use to messing things up. Don't worry, as long as we have them there's nothing that can stop the magic of friendship.” She gestures to the others as Fluttershy and Sonata help her to her feet.
“She's right as long as we're together there's nothing we can't do.” Twilight says as they share a group hug. “We have to get back to the castle. Between my friends in Equestria and you two we might just stand a chance.”
“You're right Twilight, we need to go through that portal and put an end to this right now.”
“Wait!” They turn to see Sunset, Pinkie Pie and Rarity running toward them. Sunset stops in front of them, trying to catch her breath before speaking. “There's something you need to know.”
Twilight's Castle
“Then we went on a tour of the Equestrian Rock Museum, and I have to say that was an experience I'll never forget.” Double Down and Pinkie have been trading stories about Maud the entire time Lightning Dust has been gone, much to the boredom of the other captives and guards alike. Unknown to the Shadowbolts, Scootaloo has sneaked back into the room. Making her way around quietly, she gets behind Rainbow Dash who tries to buy her more time.
“Hey Pinkie, tell them about the time Maud came to Ponyville.”
“Oh yeah. How could I forget that story?” As she regales them with the tale Scootaloo begins working on the ropes.”
“Don't worry Rainbow Dash, I've almost got it.” Just as she is about half way through the Shadowbolts see Lightning Dust and an unidentified armored alicorn come through the portal.
The three look over the new arrival. “I expected him to be a little more...colt like.” Cut Off says as the others nod in agreement.
“Change of plans gentle colts. This is Adagio Dazzle. We work for her now got it?” Lightning Dust turns to her. “You didn't tell me you were an alicorn.”
Adagio moves her hoof to her head. “I wasn't. It must have been Sombra's power.”
Dust looks around and sees Scootaloo's tail sticking out from behind Rainbow Dash. “Hey!” She speeds over, grabbing the filly in her teeth. She swings back around, dropping her in front of Adagio. “Looks like we've got ourselves a little saboteur.”
“You won't get away with this. Rainbow Dash is gonna whip your tails.” The young Pegasus says.
“Defiant. I like that. You know kid you remind me of me at your age.” Dust says.
“I'm nothing like you.”
“You soon will be runt.” She gives her a wicked smirk as she turns to Adagio. “I'll be needing some new recruits for my team.”
“Say no more. It'll give me a chance to break in these new powers of mine.” She begins to sing as her horn glows and the dark energy begins to form around Scootaloo.
“No let her go!” Rainbow Dash shouts as the others look on in terror and anger.
“Double Down you can't let her do this.” Pinkie pleads.
“I'm sorry Pinkie. It's out of my hooves.” He says, shamefully putting his head down as the process finishes. As the smoke clears they behold the filly, now wearing the Shadowbolt uniform and now able to fly under her own power.
“Scootaloo are you alright?” Dash calls as she gets no response.
“You monster!” Rarity calls out.
“Ah, my first recruit.” Dust brings her in close. “Don't worry Dash, I'll be the best mentor ever and there's a whole town full of pegasus where she came from.”
“Is this what you're willing to do just to get back at me? Ruining everypony else, even a filly just for revenge? Does it mean that much to you?”
Dust stops to think. “Yeah, pretty much. Alright we're headed for Canterlot. You three make sure that portal is destroyed. We don't want anyone else coming back through. Then take this lot to the dungeon.”
“Uh, I don't think this castle has a dungeon.” Boogie corrects her.
“Then make one!” She says, frustrated with the three. “Now if you'll excuse me, I have an army to make.”