You and Aile return to the Command Center of The Guardian Base!
Prairie: (Y/N), Aile! We've tracked down Model W's location. It's in the tallest building right in the center of the country - Slither Inc's head office. I'm detecting a huge concentration of energy amassing within the building. Something big is about to happen. It's going to be dangerous.
Aile: It probably will be, but at this point, we don't have that much of a choice.
(Y/N): She's right. We have to move.
Prairie: Listen, I know it's a little late for this, but... I'm so sorry that I didn't tell you about Giro and his mission to watch over you. Please believe me when I say that we didn't want to deceive you. Giro's face always lit up so much when he talked about you... Giro... He loved you very much.
Aile: Prairie, did you have feelings for him?
Prairie: (flustered) W-WHAT?!
(Y/N): Hey we won't hold it against you. You just look so happy talking about him.
Aile: (Y/N), I'm ready.
(Y/N): Great! Let's end this, for everyone in this country, and the man you both care about!
And with that, you and Aile arrive at Slither Inc.
Both of you take the elevators to a higher ground, and begin to reach the room containing Model W!
But near that room, there was-
(Y/N) and Aile: Cyber-Elves?! Why are there so many?
As you head in, Serpent appears.
Serpent: You must be wondering why we need so many Cyber-elves to awaken Model W... Hmph! I child like you could never understand that! Their fright... It becomes the power that drives Model W!
(Y/N): YOU MEAN- OH GOD!!
Serpent then lifts his arms up!
Serpent: Model W, it's time! The despair and fear of this country are yours!
All of the Cyber-Elves break out of the containers and begin to be absorbed!
Serpent: By joining us, the weak are freed from their suffering! The chosen one, Mega Man, will save the people! That is the glory of Project Haven!
Aile: Mega Man will save the people!? How is sacrificing the people of this country going to save them!?
Serpent: Precious misguided little girl. It's time for you to come off of your high horse. Our power is the result of many sacrifices. We are the chosen ones. It is destiny for the last of our kind to rule. Model W is not about destruction. It is about rebirth and evolution! I am the giver of meaning to the lives of people who cannot keep up with the tide of evolution.
(Y/N): The only thing you are is afraid. Afraid of your past. Afraid of yourself and what you've become! Your fear is what drives your desire to rule! You think this is evolution!? Is this really what you want!?
Serpent: You think I'm doing this all out of fear? That's nonsense! The spirits of the people have given me what I need to obtain the power of Model W! Look at her! She's only able to stand before me today thanks to the power of Model Z absorbed from that red Mega Man! Evolution requires sacrifice! The ones who will determine what needs to be sacrificed are the Mega Men!
And then-
Serpent: MEGAMERGE!!
He merged with Model W!
Serpent: Your fear and despair combined with my joy in victory... They shall be the ultimate gift to Model W!
He then attacks!
(Y/N): Aile!
Aile: Right!
You use Ultra Instinct and dodge Serpent's attacks!
He fired from his arm powerful blasts, which you counter with ki blasts!
He then does some kicks and uppercuts!
Aile follows with Z-Sabre slashes and blasts from her gun!
Aile: (Y/N)!
(Y/N): We'll finish this together!!
(Y/N) and Aile: AAAAAAAAAAGH!!!
And then you both stab Serpent in the chest!
Serpent: AAAAAARGH!
He kneels down and laughs.
Serpent: GYAHAHAHAHAHAHAHA!
(Y/N): What's so funny Serpent?
Aile: I wouldn't be laughing if I were you.
Serpent: It's just as Prometheus and Pandora said. You are the final key. Right now... you are being controlled by a powerful emotion... Emotion so powerful it exceeds even mine!
All of a sudden the room shakes and Aile demerges!!
(Y/N): Aile!
Aile: What the hell? Why can't I megamerge?
Serpent: The emotion driving you now... That emotion is not bravery... It's not born out of some sense of righteousness... It's hate. Your hate for me and everything I've taken from you!
(Y/N) and Aile: What!?
Aile: I- I'm the key to awakening the power of Model W? All my fighting and I did nothing more than fulfill some madman's destiny?
(Y/N): No, that's not true! You're a hero, Aile!
???: He's right, Aile.
???2: (Y/N) always knew what to say to people.
Model X and Model Z appear.
And so do Models H, F, L, and P!
Model H: We did not lend you our power just to let you carry out some kind of petty revenge...
Model F: Beating up someone just because you don't like them is nothing more than the action of a playground bully.
Model L: Don't give in to the hate. If you fight the flow, you just end up swimming in place.
Model P: Even in the darkest tunnel, there is always a light at the end of it for you to follow.
Model X: Your power is not based on hate. Your real power. Your wellspring of bravery lies within you!
Model Z: Look within yourself!
(Y/N): MEGAMERGE AILE!!
And Aile finds herself and-
She merges back with Models X and Z!
Aile: You're right. I made a promise to you on that day! I said I will protect the people! All of them!
Serpent: Well then. If you're so sure of yourself, let's find out which Mega Man is destined to rule the world!
Aile: I'm not interested in ruling the world! Serpent, if you want to be the Mega Man destined to rule the world, then I am the Mega Man that is destined to save it!
(Y/N): And I'm the one who's destined to guide the Mega Man who saves the world!!
Serpent: YOU FOOLS!
He begins attacking with various flame attacks, his fists, and other moves!
(Y/N): YOU WON'T WIN!!
Serpent: I WILL SUCCEED!! MEGA MEN ARE DESTINED TO TRANSCEND HUMANKIND!
(Y/N): NO!! THAT'S ONLY WHAT YOU BELIEVE!! HUMANKIND WILL ALWAYS PREVAIL!! THEY ARE STRONG!! THEY ADAPT!! THEY PROLONG!!! YOU WILL BE FINISHED!!
You break off his arms, and then let Aile get on your shoulders!
(Y/N): GO AILE!!
Aile takes out her Saber!
Aile: AAAAAAARGH!!
She stabs Serpent's core!
Aile: This is the end of the line. I will never become like you!
Serpent: Never become like me, eh? Gyahaha! You just don't get it do you? The Mega Men are all designed with one purpose, to destroy each other and survive to control Model W. It's all just a game, his game. We are all pieces on the board, and the winner becomes the ruler of the world!
(Y/N): What are you talking about?
Serpent: (Y/N), can't you see? That girl, Aile has the blood of him. The man who created Model W!
(Y/N) and Aile: WHAT?!
The Slither Inc. Building collapses as you grab Aile and start moving.
Serpent: The destiny of destruction... Still awaits... So long as you have hearts, hate will lurk in the shadows... You who possess the wellspring of emotion known as the heart... You are the true Mavericks!
And with that, Serpent dies as his body falls apart.
Outside...
You let Aile down as she turns back to normal.
Aile: His blood flows in my veins... The power within me... Is the power to control the world?
(Y/N): Aile.
???: Hey, I don't want to hear that kind of talk. You promised to continue the fight where I left off.
Giro's spirit appears.
Aile: GIRO?!
Giro: Its just blood. Are you going to let some man you don't even know decide your destiny for you? Destiny is not something that is given to us by others. Destiny comes from the concept of "destine," or directing something towards a given end. Be the one doing the directing. Only you can decide your destiny. Forget the past. It means nothing. The power you contain within is the key to creating your future.
Aile: Serpent said that my power is a result of many sacrifices... But those sacrifices didn't just give me power. The first commander who first made the Biometal... You, who protected me for all those years. The Guardians... All of your sacrifices have given me something beyond just power. They gave me the will to protect the world. And I will protect it! And ... most of all-
She walks to you.
And then-
Aile: (Y/N), I ... I love you.
She hugs you tightly, and then-
(Y/N): I love you too Aile.
And then you both kiss.
Giro: I guess my work is done. Take this world into the tomorrow you desire.
He then leaves.
(Y/N): We'll fight them. Whoever made Model W, we'll stop him.
Aile: Together.
???: (Y/N), AILE!!
Prairie appears with the other Guardians, and jumps into both of you.
And the Guardians laugh as you and Aile hug Prairie!
(Y/N): Facing our destinies and carving out the future... That's our struggle. We fight for what we believe in, for what we love, for everyone and everything we cherish.
Meanwhile...
Prometheus and Pandora stand amongst the ruins of Slither Inc.
Prometheus: So, he lost.
Pandora: He is the one, who he has been looking for.
A figure appears amongst them.
???: So, is it true? The boy was with her?
Prometheus: Yeah.
???: Well, the game has just begun. Now, Pandora.
Pandora: What is it Master?
???: Go to the facility, and find him. He'll be a part of this too.