The day it was time to march into republic city, Kuvira gave a speech to the earth empire troops before they left.
Kuvira: Today we stand on the precipice of history. For the past three years, we've fought side by side to unite the earth empire and we've proven that no one can stand in our way. Not even the Avatar. But our mission is not yet complete. There is a grave injustice that must be corrected. As you all know, After the hundred year war, Avatar Aang, along with Fire Lord Zuko stole Earth Empire land and formed the united republic. This land belongs to the people of the earth empire and it's time to take it back. Republic city will be ours!
The earth empire troops in unison: All hail the great uniter!
Kuvira turned to Baatar Jr.
Kuvira: Are you ready to show the world what a true super power looks like?
Baatar Jr: Yes. I'm honored to march into the city by your side. I love you, Kuvira.
Kuvira: I never could've done this without your help. After we claim victory, we can finally get married and rule our empire together.
Kiriko, Katsuo, Kuvira, and Baatar Jr got together to go over the plan once more. Kuvira and Kiriko were going to board the mecha suit, while Baatar Jr and Katsuo were going to wait until they surrendered to discuss the terms of surrender.
Then Kuvira and Kiriko mounted the mecha suit, and Baatar Jr and Katsuo rode over by airship.
When they arrived, Raiko projected his voice through loudspeakers.
Raiko: Kuvira, this is President Raiko. I order you to stand down. Turn your army around and leave.
Kuvira: You're in no position to give orders.
Raiko: Stand down or we will attack.
Kuvira: I don't think you understand the power I possess. Let me make it clear.
Katsuo watched from her view in the airship as the giant mecha suit shot a beam of spirit energy into the ocean, blowing up a few abandoned ships. Then shot at a few more abandoned ships in the ocean across republic city.
Then the mecha suit aimed at the troops of the united forces below.
Kuvira: You have three seconds or I wipe out your army.
Raiko: I have no choice.
Kuvira: Time's up.
Raiko: Stop! We surrender! Republic city is yours.
Kuvira: Good. Turn your army and the avatar over to me and give Baatar and Katsuo your location. They'll present you with our terms.
Katsuo: We did it! And Korra had better listen, because she lost the fight back at zaofu, therefore promising to stay out of our business for good.
Baatar Jr radioed Kuvira.
Baatar Jr: We've done it, Kuvira! And I just got word that President Raiko is on air temple island. We're heading there now.
Baatar Jr and Katsuo's airship headed for air temple island. Only, on the way there, Katsuo felt another presence. She took off her shoes and used seismic sense.
Katsuo: Intruders.
Baatar Jr: What did you say?
Katsuo: There are intruders on the roof of the ship. I'm going up there.
Katsuo found a hatch that led to the roof. She climbed up it, and was just about to reach the roof when she stopped herself.
Katsuo (thinking): It sounds like there are a lot of people up there. And how am I going to fight them? We're not on the ground. I'm not a metalbender or a lavabender like Kiriko. I'm just an earthbender.
Katsuo reached for her meteor earth bracelet.
Katsuo (thinking): This is all the bending material I have to fight them with. Will I really be able to do this?
Katsuo clenched her bracelet in her hand.
Katsuo: No matter. I have to do my best. They promised to surrender, and now they're trying to attack us. Again. This I won't let slide.
Katsuo opened the hatch and jumped up onto the roof of the airship.
There were some airbending kids up there, as well as Korra.
Korra: Katsuo? What are you doing here? And how did you find us?
Katsuo: Korra. You said that if you lost the fight to Kuvira at zaofu, then you would stay out of our business for good, and you lost the fight, fair and square. Yet here you are, breaking that promise. Not only that, but Raiko surrendered. You have SOME NERVE showing up here.
The airbender kids spread their gliding suits and shot blasts of air at Katsuo. Katsuo dodged them all and sent her meteor bracelet at them, tearing holes in their gliders and sending them tumbling to the ground.
Katsuo: Now it's just you I have to deal with.
Korra: Katsuo, why are you doing this?
Katsuo: I know what the right thing to do is, now. Don't try to change my mind.
The airship passed by a huge building made out of stone, and Katsuo smiled. She wasn't a lavabender, or a metalbender, but she was a very strong earthbender.
She bent a few boulders off the building and sent one of them flying at Korra. Korra broke it with earthbending, but it left an opening for Katsuo to shoot her meteor bracelet right at Korra and hit her with full force, stunning her. Korra fell backward, and Katsuo used the remaining boulder to knock her off the airship. Then Katsuo climbed back inside the hatch the way she came.
Katsuo: I dealt with the intruders.
Baatar Jr: Who were they?
Katsuo: Korra and a handful of airbender kids.
Baatar Jr: You were able to take Korra on yourself?
Katsuo: Korra's not as good as you think. And the airbender kids were a piece of cake. Puncture their gliders and they're done for.
When Katsuo and Baatar Jr reached air temple island, they disembarked their airship to find President Raiko and the other world leaders.
Raiko: What are your terms?
Katsuo: You will fully surrender republic city, therefore handing the earth empire back it's rightful land that you took. The earth empire will be fully united, and you'll stay out of our business from now on. We won't use our weapon against you so long as you do and all the peaceful citizens of the united republic will be dealt with fairly.
Raiko: Sounds reasonable. Where do I sign?
Baatar Jr: Here's the contract.
Baatar Jr handed Raiko the contract, and he signed it. Then he handed it to the other world leaders, and they all signed it as well, one by one.
Katsuo retrieved the complete contract with all the signatures.
Katsuo radioed the inside of the giant mecha suit. Kuvira and Kiriko picked up.
Katsuo: I have good news and bad news.
Kuvira: What is it?
Katsuo: The good news is that we signed the contract. It's done! The earth empire is fully united at last!
Kiriko: Perfect!
Katsuo: The bad news is that on the way over, Korra and a handful of airbender kids tried to attack our airship. I fought them off, but they're probably going to try and get into the giant mecha suit. Our job isn't quite complete. We still have them to deal with.
Kiriko: WHAT!? Raiko surrendered! And what's more, Korra promised to stay out of earth empire business for good the moment she lost to Kuvira in the fight at zaofu!
Katsuo: I know. I'll head over to help you in the mecha suit.
Kiriko: We WILL destroy Korra, and whoever she brings!