This is how Sci-Ryan and Evil Anna defeated Larxene in Ryan's Quest: Chain of Memories.
[Ryan is fighting them and he defeated them]
Ryan: Brother. Girls..
Cody: What some more?
[He blast his Brother]
Cody: Looks like we win.
Aria: You will be under our spell, Ryan.
Megaminé: Cody, Dazzlings. Stop.
Adagio: You are through!
Megaminé: I said STOP!!
Then Cody and the Dazzlings collapsed
Ryan: Brother? Girls? What did you do! What have you done to them!?
Then Larxene appeared
Larxene: Broke their hearts. I'd say more that she smashed them, really.
Ryan: Smashed their... Hearts?! What's going to happen next? What will happen to Cody and my three siren friends!?
Larxene: [laughs] Oh, you're so much fun to watch, Prime-prince. If it's your brother and the Dazzlings you're worried about, then don't. Because, Ryan. Cody and your three siren friends are never really here.
Ryan: What do you mean?
Larxene: Do you really think I'm just gonna say it? That's too easy! Oh, what to do?
Ryan: Shut your cake hole!
He attack her and she kick him
Larxene: Alright, then. Have it your way, Ryan. I know it'll kill you and put you offline to hear this, but, I think I can live with that. That thing laying there was just a puppet and a clone that Vexen made as an experiment. No more then a toy. It's laughable really, they called you a fake and a copy, but they was fabrications all along.
Ryan: Not my brother? Not my three siren friends? Clones? And a Fake?
Larxene: Fake in every possible way. And clones as well. They were only finished recently. How could they remember everything?
[She pick them up]
Larxene: You get it? Their memories with Megaminé were just planted, not real.
She throw them to the wall
Larxene: Yup. That means, all this time, it's been picking fights with you over memories---that were counterfeit, trumped up, and completely bogus. Isn't that the truth, Meagminé?
[Larxene looks at Megaminé]
Larxene: Oh, so cute...but behind this little face, you do awful things.
Larxene: You're so stupid. Don't you get it now? That's what Megaminé's powers are about! She can enter, rearrange, and even create new memories---of anything, even things that never happened. The girl you've been trying to protect all this time---is really a manipulative witch who shackles people's hearts!
Ryan: Then... my memories... are all... Just made up?
Larxene: Oh, you do get it! Lies, lies, all lies! Just Megaminé's illusions, nothing more. Binding you in the chains of your own memory was central to our trap. It makes me tingle to think how easily you were duped. So close to it--- we were almost there. This was our only chance to turn the Prime-prince into our puppet, but--- That jerk Axel---he used Megaminé to betray us!
[She summon her knives]
Larxene: So now, I'm left with no choice but to eliminate you!
Ryan: You'll regret it for this.
Larxene: Huh? It's a little late for the witch to grow a conscience. Last time I checked---YOU'RE the one who fooled around with his memories creating this mess.
Megaminé: I get what you mean. But...
Larxene: I should tell you that I'm in an EXTREMELY foul mood. Thanks to you, all our plans are ruined!
[She knock her over]
Larxene: What's this? Are you upset? (Giggles) And you don't even actually know her!
Ryan: Not so.. I think... the thing I made... is a promise.
Ryan: The reason I made a promise is to keep Megaminé safe. Even though my memories are made up and.. I think... the promise I made is 100% real to me. That is why I keep it. It's my vow.
Larxene: Hmph. You're such an idiot. There is no promise and there never was! You're just delusional. Must you insist on playing the hero? Whatever. If that's the way you want it... You're going down alone!
[Evil Ryan taps Larxene and she turn around]
Evil Ryan: Remember me? BOO!!
[Sci-Ryan heals Ryan]
Sci-Ryan: Not if we can stop you!
Evil Anna: Sci-Ryan's right!
[Ryan looks at his friends]
Ryan: Guys! You found me!
Evil Ryan: Sure we did, Ryan. We were worried about you.
Bertram T. Monkey: And we promised, Ryan. We promised that we would protect you.
Ryan: Yeah. [to Sci-Ryan] Sci-Ryan? You and Evil Anna fight Laxene while I recover.
Sci-Ryan: You got it.
Evil Anna: You will never be alone, Ryan. It's always been the 7 of us and we stick together.
Sci-Ryan: And that is how it's going to stay!
Larxene: Ok. Have it your way! More pain for you means more fun for me! [to Sci-Ryan] You will be my girlfriend, Sci-Ryan!
Sci-Ryan: Un guard!
They are fighting her and they defeated her
Larxene: No. No! I refuse to lose to a Crystal Prep student and his siren girlfriend! I think I'm... I'm fading?! No, this isn't... the way I... I won't... ALLOW!
She fading away and our Heroes look at Megaminé
Crash: Well. You must be Megaminé. It's great to meet you. We're friends of Ryan, I'm...
Megaminé: Crash Bandicoot. Evil Ryan. Evil Anna. Sci-Ryan. Matau T. Monkey and Bertram T. Monkey.
Bertram: That's right, and how did you know our names?
Spikewave: Well, good job, Ryan. You found your friend. You should be happy for this.
Ryan: If I were, I don't think so. Megaminé, can you tell us what's going on?
Megaminé: Of course, it was my fault, after all. I took all the People and memories, that were inside of Ryan's Heart... and little by little, I replaced them with false memories.
Sci-Ryan: Hey, what about Ryan's Promise?
Megaminè: Made up. It was a fake. Ryan didn't promised me anything, me being with him at Canterlot High... it was a lie. We never met, it was not Ryan's friend.
Ryan: And you weren never anything more--- Either-
Megaminé: No, you see. In all of your true memories. I was never really there.
Spikewave: So that mean it was your magic that made us lose our memories. Is there anyway for us to get them back?
Megaminé: I can fix everything, Spikewave. If we go to the 13th floor. But, Marluxia he...
Sci-Ryan: Bet I know who that is. Was he the one who tampered all our memories?
Megaminé: If I didn't obey, he said I'll be lock in this castle forever. I been... Alone for so long.
Evil Ryan: So, you did what this chap told you to do because you're alone?
Megaminé: I'm so sorry.
She's gonna cry
Ryan: Hey. [comforts Megaminé] There, there, Megaminé. Shhh. Don't cry.
Megaminé: Oh... of course. I know I really don't have the rights to.
Ryan: That's not what I meant.
Ryan: It's like this... I'm really not happy about you messing with my memories. But...you know---I can't really get mad at you for it, either. These memories you gave me... In my head, I know they're lies---but they still feel right. Like the promise I made. I said I would protect you and that I wouldn't make you cry...not ever. Megaminé...if you cry now---I'll feel guilty, like I let you down. So don't cry...please. Until I get my memories back, smile and try to be happy. It's easier on me that way.
Sci-Ryan: Oh boy. This is too much.
Crash: It's okay. Ryan's always like this every time he's around girls!
Ryan: Guys, cut it out! I thought you guys have lost all of your memories.
Matau: Well, too bad. Good friends don't forget the good stuff.
They laugh even Megaminé
Ryan: There! That's it! That's the Megaminé I remember. Yeah...I really liked it when you used to smile. Of course, that was really only in my fake memories. But what I'm feeling now definitely isn't fake. It's real.
Megaminé: Thank you.
Ryan: Come on, you guys. Let's go!
Sci-Ryan: Yeah! I can't wait to get all my memories back!
Crash: Megaminé, Marluxia is gonna be up there. So maybe you'd stay down here?
Ryan: And do one thing. Make sure these 4 recover.
Megaminé: Okay. Please be careful, Ryan.
Ryan: I'll be okay... I promise.
They went off to the thirteenth floor