Luna had noticed she had been developing some strange symptoms lately. When she told Lucy about them, she suggested for her to get a pregnancy test. She did and found out she was pregnant with hers and Natsu's first child. They were finally going to become parents! But amidst all this joyful news was also concerning news. Luna and Natsu were at the Fairy Tail guild for a celebration for successfully retrieving Makarov from the Alvarez Empire. As they were celebrating, Makarov brought up his concern about Zeref and the Alvarez Empire and that they were planning on invading the Kingdom of Fiore. Natsu encouraged everyone, saying that they would protect their guild again like they had done before in the past. Just as Makarov was going to go into more detail, Mavis Vermillion appeared and explained her past with Zeref and the purpose of Fairy Heart. It was essentially a source of infinite magic. Natsu was particularly shocked to hear about it. Makarov and Mavis then explained the Alvarez Empire's intentions with Fairy Heart: to use it to defeat Acnologia, but it would also make them an unstoppable force and threat. Mavis then told the guild she was sorry that her sin dragged Fairy Tail into this whole mess. But everyone was all for protecting Fairy Heart, saying that if it wasn't for her, they wouldn't all be together today. Then they started pondering how they were going to defeat Zeref since he was immortal.
"How do we defeat someone like that?" Erza thought out loud. Natsu then jumped up on the table with a chuckle. Luna hopped onto the table with him right after.
"Just leave that part to us you guys. We'll be the ones to take down Zeref. Because our right arms are secret weapons too!" Natsu said as Luna nodded with a determined smile on her face.
"So...?" Lucy started to say.
"Tell us more about these secret weapons." Erza finished Lucy's sentence.
"Well, it's a secret." Natsu replied.
"What?" Lucy said, kinda confused, disappointed and slightly annoyed.
"That's why they're secret weapons." Natsu said as Gray and Gajeel grabbed him off the table and started fighting with him.
"Just tell us what it is ya pink haired punk!" Gray yelled at Natsu, trying to force him to spill the beans.
"How the hell can your right arms be a secret anyway!" Gajeel yelled at him as well. Lucy and Erza pulled Luna aside while the boys tussled.
"Looks like Natsu's not going to say anything more on it. But you'll tell us though, right Luna?" Lucy asked Luna who sighed and shook her head.
"Sorry guys. I promised Natsu I wouldn't tell a soul." Luna said as Lucy and Erza sighed in disappointment.
"All I can say is that it's a one time use technique. With this, we'll be able to take down ol' Zeref once and for all. There's no way we're gonna lose to him." Natsu said as Luna nodded in confirmation. Makarov then continued to share what he knew about Alvarez, particularly the Spriggan 12, the twelve most powerful mages making up the elite unit that served Zeref as his personal guard. Once he was finished, the Fairy Tail mages started forming their strategies based on the information they had.
~Time Skip~
Luna, Natsu, Happy, and Elise went into Lucy's apartment to see what she was up to since the evacuation was finished. She was in the middle of writing about Fairy Heart and the incoming invasion from the Alvarez Empire's forces. They snuck up behind her to see what she was writing.
"Pretty good stuff there Lucy." Natsu said in a joking tone.
"If you keep it up, you could turn into a real novelist someday." Happy chimed in.
"Wow, you really have a way with words Lucy." Luna said impressed by the way Lucy worded her writing.
"Yes very impressive." Elise said as she hovered next to Happy. While Natsu's and Happy's words were more of a joke, Luna and Elise actually meant what they said. Natsu and Happy then repeated Lucy's written words in a joking dramatic tone which she wasn't very happy about.
"There's a difference between being together and breaking and entering!" Lucy shouted as she kicked the chair at Natsu and Happy who both dodged it.
"You should try to relax a little." Natsu said as the chair crashed into the fireplace behind him.
"The tone is all empty and boring so we decided to come over here." Happy said, referring to the lonely atmosphere of the evacuated town.
"Sorry about them Lucy. Elise and I actually meant what we said." Luna apologized to Lucy before giving Natsu and Happy a glare.
"It's okay, you don't have to apologize Luna." Lucy said to her with a small smile. Then Lucy's facial expression turned a little more serious.
"Well I'm glad they were able to evacuate all the citizens at least." Lucy said. The two dragon slayers and their exceeds noticed that she was stressed over what was to come.
"Cut loose Lucy. Let's have some fun!" Natsu said with a goofy smile, trying to lighten her mood.
"Yeah come on! We brought a whole bunch of games and stuff!" Happy said excitedly. Lucy sat down and crossed her arms and legs.
"You know, we're going into a huge battle with a terrifying enemy tomorrow. I'm not feeling games. And unlike the four of you knuckleheads, I'm really not feeling all that excited about fighting either!" Lucy said to Natsu and Happy. Happy gasped in disbelief at what she just said.
"I'm not excited about the war!" Happy stated. Natsu's expression turned serious.
"I don't think you understand something about me. I mean, I enjoy a good fight, but only when it's a competition. I hate it when it involves death like this one. Giving it everything I've got to show how much I've grown is what I live for. But this time is way different. I'll do anything for us to win. Or else we won't survive this." Natsu said as Luna nodded. Lucy's facial expression softened and her lips curved into a small smile.
"Plus there's something I really wanna do when it's over." Natsu said with an excited smile.
"Aye!" Happy chimed in.
"I know you're dying to hear what it is Lucy." Natsu said looking at her.
"Nope! Stop right there. Don't say a thing. This is actually a classic literary technique we writers call foreshadowing." Lucy said.
"What does that mean?!" Natsu asked loudly.
"Like when someone talks about their future plans right before something big. But then a tragedy strikes and prevents them from filling their dream.
"We're not scared to talk about the future." Natsu said.
"Aye!" Happy followed.
"Igneel himself told me I should always talk about it. Because that's what gives us the strength to make it there." Natsu said with a determined smile.
"Prisma told me something similar. She told me that thinking about our future plans is what gives us the hope and motivation to push through whatever it is we're going through so we can be there to put those plans into motion." Luna added.
"That's a nice way to look at it." Lucy said as her smile brightened.
"Alright! Let's play some games!" Natsu said excitedly.
"Who's into strip poker!" Happy said with equal enthusiasm.
"Not me you freaky cat! Besides, you're already naked!" Lucy shouted angrily at Happy. After Natsu and Happy started their game of strip poker, Lucy, Luna, and Elise sat on the bed talking.
"Should you really be fighting, Luna? I mean, you're carrying yours and Natsu's child." Lucy said, concerned for her best friend and her baby. Luna sighed as she looked down.
"We're already at an overwhelming disadvantage. We need all the strength we can get. Even though I'm pregnant, I have to fight. Natsu said he'd do anything if it means our survival of this war. And I feel the same way." Luna said, clenching her fists in her lap.
"We all do." Elise said, putting her paw on Luna's leg.
"Yeah, I guess you're right." Lucy said as she grabbed a book to read and laid on her stomach on her bed. Suddenly, they sensed something outside which signaled the arrival of the Alvarez Empire's forces. Shortly after, Luna and Natsu were dispatched with Wendy and Gajeel and their exceeds as the Flying Dragon Squad to take on the enemy airships. They destroyed many of the ships as they dodged the magic missiles fired from them. Bisca of the Osprey Squad fired the Jupiter canon at the aerial fleet. Ajeel Rami, one of the Spriggan 12, scattered the shot but it still destroyed some of the ships. The dragon slayers decided to go after the sand mage Ajeel since he was going to be the most troublesome. But they were immediately affected by their motion sickness when they landed on the airship. Ajeel then approached Natsu, grabbed him and mocked him. Then suddenly, Erza showed up and cut the bow of the ship off, causing Luna, Natsu, Wendy, and Gajeel to plummet along with the front of the ship. Elise, Happy, Carla, and Panther Lily swooped down and grabbed their respective dragon slayers and left Ajeel to Erza and went for the airships that had landed on the ground. There, they fought the soldiers disembarking from the ships. There was one particular guy that was giving Natsu a little trouble.
"Come on Natsu, get serious would ya! Normally you would've put the hurt on a pushover like this by now, so what's the deal?!" Happy said.
"Yeah I know. But still, there's gonna be more of these clowns to take out. I gotta be smart. I can't go full on from the beginning." Natsu said as Happy looked dumbfounded and shocked. After wiping out several soldiers with her ice dragon slayer magic, Luna looked back and smiled at Natsu, proud of how much her husband had matured. Once they had seemingly defeated the enemies in the area, their captain, Bakel, suddenly popped up behind Natsu.
"Give up now! Bwahahahahahaha! How can you beat our army when this is all you've got?! You losers can't even handle the Ajeel Division!" Bakel said as he landed his fist on Natsu's head. Wendy and Gajeel looked worriedly at Natsu. Luna, on the other hand wasn't too worried about him. She knew him better than anyone. A hit like that would definitely take out a normal person but not her husband. He wasn't even fazed by the surprise attack.
"We can't, huh?" Natsu said as Bakel looked at him confused before he was elbowed hard in the gut. Before he knew it, he was sent flying upward into the sky by Natsu's raw punch, not even using his fire magic. Shortly after Bakel crashed through Ajeel's main airship a huge sandstorm covered Magnolia and more enemies were approaching. And though all the sand blowing around made it extremely difficult to see, Luna and the other dragon slayers relied on their keen sense of smell to locate their enemies. Just then, a bright twinkle of light shone in the air through the sandstorm. It was Erza's morning star armor. Bisca fired the Jupiter canon and the sand cleared not long afterwards due to Erza taking down Ajeel and his airship. She began falling through the sky and Natsu ran after her and caught her just in time. He gently set her down and asked if she was okay to which she responded and raised her fist in the air victoriously which put a smile on his face. Natsu then informed Fried Justine that all the foes from the west had been defeated.
~Time Skip~
The next day, Natsu, Happy, Luna, and Elise sped off to go face off against Zeref. They soon found his personal army. There were so many soldiers, they looked like fibers of a moving carpet. The two dragon slayers proceeded to tear through the "carpet" of soldiers like it was nothing. Luna used her Great Ice Dragon Queen's Roar to freeze a huge portion of the army in place then Natsu used Fire Dragon King's Roar to burn the soldiers that were immobilized by the ice. Suddenly Zeref showed up and ordered Invel Yura, one of the Spriggan 12, to withdraw the rest of his army. Natsu and Luna told Happy and Elise to retreat as well as they both unwrapped the bandages on their right arms, revealing dragon tattoos. Natsu's tattoo resembled Igneel and radiated extreme heat and magic power. Luna's tattoo resembled Prisma and released a frigidly bitter cold magical energy. Natsu then charged at Zeref and burned away his black magic while Luna used her Great Ice Dragon Queen Mode moves to hinder the black wizard, allowing Natsu to gain the advantage and overwhelm Zeref though he did receive a large gash on his right cheek. With another clash, Zeref, Natsu, and Luna were pushed back away from each other.
"How very surprising. Seems like you guys have developed a new skill." Zeref said, seeming impressed by Natsu's and Luna's newfound powers.
"Our parents Igneel and Prisma gave it to us. This is the last of their powers. We've been holding it. We spent ten months in training just so we could release it now." Natsu explained as Luna nodded her head.
"The last of their powers you say?" Zeref said.
"That's right. We have to make it count. Because once it's gone, it'll never come back. Every last bit of Igneel's and Prisma's determinations in one shot." Natsu continued as both his heat and Luna's cold started to expand and dance together in a massive deadly aura of fire and ice. Zeref just stared as if he were in awe. Suddenly, Natsu turned to Luna.
"Luna, I need you to please get back. Leave Zeref to me." Natsu said as Luna looked at him confused.
"But Natsu, this is what we trained for! To defeat Zeref together!" Luna protested.
"I know, but that was before you got pregnant. I don't want you or our child to get hurt. Besides, you've helped me plenty." Natsu said as he signaled for Elise to take Luna back a safe distance.
"Okay... but let me do one last thing for you." Luna said as she held her hands out in front of her and aimed them at Zeref.
"Great Ice Dragon Queen's Shackles!" Luna said loudly as she formed ice chains and shackles that latched themselves around Zeref's wrists and ankles and anchored him firmly to the ground just in case he was going to try to dodge Natsu's finishing attack.
"Thanks Luna. Elise keep her a safe distance from here. I'm gonna turn this whole area to ash." Natsu said as he focused his eyes on Zeref and Elise carried Luna up high by where Happy was. Natsu's searing heat then spread, transforming the ground itself into fire. Even in the extreme heat, Luna's ice shackles were so cold, they didn't really melt. Natsu powered up and readied his attack and lunged at Zeref and punched him with all his might, a huge cloud of smoke covered the area. When the smoke cleared Natsu could be seen kneeling on the ground and panting. The ice shackles had shattered and evaporated from the impact of his intense attack. And Zeref was still standing there, weakened but alive.