The chosen kids had collapsed from exhaustion so they had returned to their respective Ultra forms inside the sphere that Ho-Oh held. The last battle had been quite intense and they needed to rest.
"The Ultra form?" Rose asked, "I thought we were out of strength."
"You have constantly evolved and reached the greatest maturity of a Pokémon," Ho-Oh explained, "No wonder it is your normal form."
"What do you mean?" Zack asked.
"That we've progressed so much that the Ultra form is our new base form," Dylan deduced.
"That's pretty much it for me," Rex laughed.
Everyone followed them laughing, even the legendary Pokemon. It was good to do it after all the cruel battle.
"We're here, chosen children," Ho-Oh announced.
The kids looked below: there, full of Pokémon holding flags and celebrating confetti, not to mention everyone shouting in celebration, as their heroes returned alive, victorious but exhausted. The legendary bird descended until the sphere around it collided with the ground, causing it to gently release the kids.
As soon as they had touched land, the kids found themselves surrounded by all the inhabitants of Paradise. However, there were also some surprises...
"Rex!" a couple of voices shouted. From the crowd, Rex could see Fulvius and Bedelia, his parents, who headed at full speed with his son.
"Mom! Dad!" the exhausted Charizard greeted them with happiness, "You're here!"
"Well done, my son," his father congratulated him, "We saw the entire battle, I am proud of you."
"Zack!" he called another voice to the Luxray. When he saw who it was, he exclaimed:
"Damini! "How come you are here?"
"My father gave me permission to come see you," she replied, "After all, we are friends, right?"
"Of course"
"Rose!" shouted a voice from above. The girl could then see Tropius, flying in her direction, with Budew and Roselia riding on his back.
"Tropius! Budew! "Miss Roselia!" Rose greeted them, with open arms, or rather, with vines extended.
"Miss Rose!" said Budew, "The meadow blooms again!"
"Oh really? What a great news"
"No news is better than that you are well," Tropius told her, "I was worried when I saw you disappear, but I knew you would return from that darkness. I always knew it"
"Thank you for trusting me, Tropius."
"Hey, rookie!" he called a voice to Dylan. He was another Greninja.
"Isamu!" Dylan exclaimed, "Is that you? What happened to the sensei?"
"Resting with herbal tea in the dojo. He said he was too old to come, so I came in his place."
"Ha, well... I'm glad the teacher is okay at least."
"Miss Mina!" A Nidoran greeted the chosen Nidoqueen, this one she came with her mother.
"Jin!" Mina told him, "Have you come here with your mother?"
"We couldn't stay when we saw the battle in the sky," Jin replied.
"She insisted on coming, I'm sorry," her mother said.
"Mr. Luke!"
From the air, he came flying with his parents Unfezant, a little Pidove that Luke recognized instantly.
"Theo!" She welcomed him cheerfully, "I thought they were going on immigration."
"My parents allowed me to come see you one last time," explained the chick.
While they were still gathered celebrating and talking, Mew and Xerneas himself made their way out of the crowd, along with the three swordsmen (Cobalion, Virizon and Terrakion) and Keldeo.
"Many merits to you, chosen children!" exclaimed Xerneas, "You have defeated the source of all darkness and mastered the powers of the fruits of life. "They have proven without a doubt to be the bearers of light."
"We are eternally grateful to you, chosen friends," Mew continued, "You have saved both worlds from a wave of darkness."
"We finally defeated the dark matter," Rex asked, "So there are no more enemies, right?"
Xerneas and Mew looked at each other in silence, which worried the chosen ones.
"Yes, you have destroyed the dark energy of Dark Matter," Xerneas explained, "However, Dark Matter is a gathering of negative feelings from the Pokemon and human worlds, which gathers in the void where you defeated it. That is why your fruits of life were the best weapon against this being"
"It means…" Luke said.
"That, sooner or later, dark matter will return," said Mew, "It has happened before, and there are always phenomenas that relate to its supposed return."
"Then we will have to face him after a few more years?" Rose asked, "Or will other chosen ones defeat him?"
"We may have to turn to other chosen ones... But the consequences it has unleashed are also worrying: its latest return has exposed the existence of our world, and other humans with dark hearts may follow in the footsteps of the first and try to use Pokemon for evil purposes. This may increase the possibility of Dark Matter returning."
"Wait Mew, isn't there a way to avoid this last one?" Dylan asked.
"In fact, there is a way," Ho-Oh commented, so everyone paid attention to him, "If we unite my rainbow powers with the lights of the chosen children, we can erase all human memory of what happened to the Pokemon."
"And we?" Katie asked.
"Since you also have a Pokemon heart, that power will not affect you."
"Even so, human curiosity will prevail," Xerneas stopped him, "Humans always have that curiosity to know more than they should and that could lead them to the same thing. However, there is a way to avoid that, of course at least one of you, chosen children, sacrifices for it."
"Sacrifice us?" all the kids asked.
"It's not exactly a sacrifice," Mew explained, "But we can seal the barrier between both worlds, perhaps permanently. You see, the devices you have have several functions and one of them is to serve as a key. If at least one Pokephone and its chosen one is in the Pokemon world and one or more others in the human world, both will be able to seal the door that connects both worlds.
"But that would mean…" Zack deduced, "That one of us… will stay?"
"So, it seems that way…" Rex concluded, "Well, I guess you guys will have to go back, I have to be the one who stays."
"But Rex, what about your parents?" Katie asked.
"I will miss them too, but... as I said before, the time I didn't have with my biological parents I won't be able to get back, that's why I want to live a new life with them. Please understand"
Dylan, Rose, Zack, Luke and Mina agreed with the decision Rex wanted to make. Katie, seeing Rex's determination again, had to accept it again.
(A few minutes later, in the human world...)
Several people were still looking at the sky, looking for signs that the battle they had witnessed had ended in the best way. Among them, the parents of the protagonists were anxiously awaiting the return of their children. Great was his surprise when a rainbow light appeared in the sky and from it emerged Ho-Oh, with his magnificent sun feathers.
For a moment, everyone feared that the Pokemon would attack them, even the nearby armed forces that were there with the president. However, this one stopped any attempted attack, as the Pokemon's glow also made one feel hopeful. For his part, Ho-Oh landed and revealed the 7 chosen young children between his wings.
There is no need to describe the happiness of each boy or girl and his or her family at being reunited safe and sound, so we will get to the point: Rex had a long and serious conversation with his parents.
"Mom, dad... I must return to the Pokemon world," he told them, "And I will stay there, maybe forever."
"What?!" asked his father, "Aren't you coming home? Besides, you still have to finish school…"
"I know, but…" he sighed deeply, "If one of us does not stay, this whole disaster may repeat itself: at least one must stay to seal the barrier between the worlds."
"But why you?"
"Also... I found my birth parents: they're Charizard and so am I. I belong to that world and... I want to recover the life I didn't have. Understand it, please"
"I always knew you were special," her mother said calmly, "Go ahead, you can go."
"Dear! How can you...?" her husband asked.
"We knew this moment would come, so we had to let Rex choose, remember?"
The adoptive father realized his mistake, so he accepted the decision of his adopted son. For her part, the mother approached Rex.
"You're going to have a little brother," she told him.
Rex froze, because it was something he had wanted for a long time. However, he still wanted to go to his biological parents.
"We'll call him by your name, if you don't mind. To always remember you" she finished.
"Thank you, mom, dad," Rex told them through tears and hugging them for the last time. Then, he proceeded to go with Ho-Oh. But before arriving, his friends intercepted him.
"You're not planning on leaving without saying goodbye, are you?" Zack told him, putting a fist in front of him.
Rex changed his face to one of laughter.
"Of course not," he replied and put his fists together, the others did the same, like a true circle of friends.
"We will miss you," Luke told him.
"Protect the other world," Rose told him, "We will try to protect this one."
"Enjoy life with your loved ones," Mina told him.
"Our bond will never be lost," Dylan said.
"Rex..." Katie started to say, but she didn't have the courage to say it.
"Don't worry, I'll be fine," he told her, "It's probably not goodbye, but see you soon."
"Rex, we must return," said Ho-oh, "The barrier should be restored shortly."
"Okay, I'm coming!"
Rex separated from his friends and approached Ho-Oh again.
"Go with him, Katie," her mother told her, to her surprise.
"Mother?" she asked, "Why are you telling me that? What will happen to you?"
"I finally found someone's love," she replied, showing him an engagement ring, "I already lost the one I loved once when I decided not to go with him... it took me years to love someone again. Therefore, I don't want you to suffer the same: go with who you really want."
Katie shed tears and hugged her adoptive mother. Then, she ran towards Rex, who was surprised.
"Katie, are you sure about this?" he asked her, once she had explained the situation to him.
"Unlike you, I didn't have many adventures, so... you won't mind if I go with you, right?"
Rex didn't respond, he just extended his hand for her to accompany him. Now, together with Ho-Oh, they were lifted up again and enveloped in a bright aura, straight into the sky. When it reached the top, it stopped.
"Now!" Dylan shouted, pointing the Pokephone.
The others did the same and they shone one last time in the direction of that bright point in the sky. When the rays collided, the sphere released a large wave of positive energy that spread throughout the planet (unbeknownst to the people), wiping the memories of all its inhabitants and making them forget everything they were not supposed to know.
When it finished, the sphere faded away and revealed a clear, cloudless and sunny sky, like the beginning of summer vacation.
(Years later...)
"And that was the end of the adventure," a teacher told a group of children.
"And what happened to the other chosen children, teacher?" one of the children asked him.
"Well, Dylan wrote an adventure book, based on the adventure he lived; Mina created her youth women's soccer group; Rose founded her own floristry and fashion clothing line; Luke dedicated himself to traveling the world helping many people."
"And Zack?"
"He became a teacher and coach," he responded, "And he teaches the children the importance of friendship and teamwork.
"Like you?" another boy asked.
"Yes, like me"
Another boy raised his hand.
"And what happened to Rex and Katie?" he asked.
"As far as I can tell, they got married and had a son. "They even wrote a letter about it to their friends."
Finally, another boy asked.
"Excuse me, professor," he said, "Is that story real or did you decide to make it up?"
"Well, I'll leave it to you."
Just then, the school bell they were at rang, and the kids began to leave the school. For his part, the professor remained silent for a minute while he watched them leave, while in his hands he caressed a special device: an old Pokephone.