"Okay, let's try it again!" Ash called. "Litten, your turn!"

"I look forward to the point where I get to attack again," Litten said.

"Well, you can use your attacks," Ash pointed out. "You can even use them to defend yourself! It's just not going to be directly attacking Salandit because we're working on making sure this combination move works properly."

"I know, I know," Litten said, tail lashing. "Right, I'm ready."

"And… go!" Ash called. "Liechi!"

Salandit exhaled, sending out a waft of spicy, sweet scent which plumed out towards Litten.

"That's already faster than it was before," Rowlet observed. "You're doing great!"

Litten watched the puff of scented smoke approach, then paced to the side just as Salandit raised his tail and touched the cloud off with a whoom.

A pulse of green energy followed the path of the cloud for a moment, and Ash frowned.

"Huh," he said. "I wonder…"

"Something up?" Salandit asked.

"Don't worry, it can come later," Ash replied. "I was just thinking about maybe making the cloud have a different shape and making it make a spike of the energy that doesn't have to just be within the cloud! But that's for after you've really got the hang of it. Now, Starf!"

Another puff of scent, then a wham of telekinetic force. Litten easily avoided that one, too, and she smirked.

"Now, don't set them off just yet," Ash amended. "Kee first, then Ganlon – and keep an eye on how Litten is moving, see if you can make her run into one of the clouds!"

"I can hear you, you know," Litten yowled.

"Yeah!" Ash agreed. "Which is the best way to practice because if it works on someone who knows it's coming it'll still have a chance of working after someone figures it out!"

Litten demonstrated the flaw in that thinking by setting one of the clouds off herself with an Ember.

"Good point," Ash admitted. "Hmm… we'll keep practising, but I'll need to think about that a bit. That's what the shaped explosion can be for… anyway, Litten, great idea, but let's not do it for now, okay?"

"Fine, fine," Litten said, rolling her eyes.

Pikachu shrugged. "Hey, at least we're not doing this underwater."

"Don't even joke about that!" Litten requested. "It wasn't a joke, was it. That's going to be… erf, well, at least I'll be ready for it."

She then found that she wasn't ready for a cloud of Watmel-smelling smoke to drift over her, and Salandit set it off with a whoosh of Fire-typed explosive energy.

"Good choice," Ash said, as Litten made a feline mrowl of disapproval. "It's a bit impolite, but I didn't say stop… okay, Belue!"

"Got it, boss," Salandit agreed.

"Hey!" someone called.

Ash, Pikachu, Litten, Salandit, Rockruff, Rowlet and Zygarde all looked along the beach, where there was a very annoyed orange-haired boy of about Ash's age storming along the sand.

"Alola!" Ash called. "Is something wrong?"

"Is something wrong?" the boy repeated. "Is something wrong? Of course there is!"

He stomped all the way up to Ash, and pointed a finger at him. "You took my chance from me!"

"Your chance for what?" Ash asked, confused. "I don't think I've met you before, but I do sometimes forget. What's your name, that might help?"

"Cross," the boy said. "And no, we haven't met, but… I spent years trying to prove myself! To show Ho-Oh that I could be the Rainbow Hero! Then I find out that you caught him, so I never could be the Rainbow Hero, and when I finally learn where you are it's right back here in Alola where I'm from!"

He clenched a fist. "And you even act like there's nothing wrong!"

"Uh…" Pikachu began. "To be honest, it's quite possible Ho-Oh just forgot or something."

"That does sound like him," Zygarde agreed.

"What's a rainbow hero?" Rockruff asked. "Because Ash definitely has a Ho-Oh, but is that the only Ho-Oh? Rainbows sound like the kind of thing Zapdos would do, too, she likes weather moves."

"Why aren't you saying anything?" Cross demanded, as his Lycanroc and Incineroar came out of their Pokéballs.

"I was listening to what my Pokémon had to say," Ash explained. "And Zygarde, they're not my Pokémon but I listen anyway."

"You do," Zygarde agreed. "It is usually woof."

"What kind of-" Cross said, then shook his head. "Whatever-"

"I could get Ho-Oh if you want?" Ash suggested. "And Lokoko, maybe? That way you could talk to him and try and work it out."

"So, uh… have we stopped training?" Litten asked. "I just want to be sure."

Salandit had left to go and get a snack.

"I don't really get why your trainer is the Rainbow Hero at all," Cross's Incineroar said, leaning down and sneering at Litten. "I remember being a Litten and I'm pretty sure I was tougher than you."

Litten tilted her head. "What, really? You don't get that I'm a new Pokémon for him?"

"No, I just don't get why he bothers with a weak Pokémon like you," Incineroar said. "That's why there's only two of us on Cross's team. He knows what a tough Pokémon is like and doesn't bother with the weak ones."

Litten hissed.

"That's not how it works with Pokémon at all, though!" Ash said. "I've got a Pokémon who's strong now, but when I first met him he was really weak because he wasn't used to being a Pokémon at all."

"How is that even…" Cross began, then stopped and folded his arms.

"Yeah, tell yourself whatever you want," Incineroar said, dismissively.

"Wow," Rockuff said quietly, looking to their side at Cross's Lycanroc. "I don't think I've had to actually say something like this before, but your teammate is somewhere between a prat and a douchenozzle."

"I wouldn't say that," Lycanroc replied. "I mean, not where he'd hear me, anyway…"

Ibid returned with two 'balls, and Lokoko came out of one.

Then Ho-Oh emerged from the Timer Ball.

"Just to be clear," he began, looking at Ash first. "This is not a reincarnation situation? Suicune would probably object."

"That's right," Ash agreed. "Cross is upset he wasn't the Rainbow Hero."

Ho-Oh turned his attention to Cross, and gave the Alolan trainer a careful look over.

"Well," he said, eventually. "It is, technically, within the bounds of possibility that you could have been the Rainbow Hero."

Cross turned to look triumphantly at Ash, but Ho-Oh kept talking.

"However, for that to happen there would have to be a significant event."

"A significant event?" Cross asked. "Like what? I'd have to take your feather to the shrine on top of Mount Tensei? I already knew that!"

"No, not quite," Ho-Oh replied. "It would have to be some kind of major incident… perhaps some sort of massive worldwide volcanic eruption?"

Cross looked blank.

"I apologize for the lack of clarity," Ho-Oh said. "I'm having trouble deciding exactly what kind of disaster would be significant enough to leave you as the best choice available."

"Do you think this is some kind of joke?" Cross demanded in a strangled voice, rounding on Ash. "This isn't some kind of game you can get out of with one of your stupid illusion Pokémon!"

"Ho-Oh's not-" Ash tried, but Cross punched Ho-Oh.

Ho-Oh's Illusion did not burst, mostly because he didn't have one. One of his feathers did come off, though, and began glowing a deep violet colour.

"Marshadow, do not touch that," Ho-Oh instructed, calmly. "We are probably going to need to get the Lake Guardians to sort it out."

"I'll call Dawn and see if she's got Azelf available to get the others," Ash volunteered.

Cross looked like he couldn't quite believe what he'd just done.

"You tell him, boss!" Incineroar said. "He hasn't vaporized you yet, that means he's weak!"

"Do you actually want Cross to get blown up, is that it?" Lycanroc demanded.

"No?" Incineroar replied, sounding honestly puzzled. "I'm encouraging him! You know, it's just like he always says!"

Lycanroc put his paw over his muzzle. "I think my teammate and trainer are a bad influence on one another."

The Lake Guardians appeared, and Mesprit inspected the simmering, corrupted Rainbow Wing.

"Yeah, good thing you called us," they said, and booped the Rainbow Wing. The corruption all discharged at once, negated by Mesprit's powers, and the Psychic-type brushed their hands off.

"Job done!"

Then Arceus appeared in a flare of golden light.

"My kohai informed me of a problem," xie stated, then examined Cross.

"What's a kohai?" Rowlet asked.

"Probably a pronoun or something," Pikachu replied.

"I believe you might do," Arceus said. "I have been looking for someone to go and get amnesia and become a Pokémon and save the world. Not this one, a different one."

Cross was silent for several seconds.

"That would mean being a hero, right?" he asked, in a sort of this-is-happening voice.

"Indeed," Arceus confirmed. "Assuming you were successful."

Xie considered Cross levelly.

"Charmander, I think," xie said. "Your Pokémon can come as well, if they wish it… in fact, perhaps this decision should be made in private."

Arceus vanished, as did Cross and both his Pokémon.

"Now let's try Mago!" Ash said. "Ready, Salandit?"

"I am a little bit in awe right now," Salandit replied, then took the last bite from his sandwich. "Anyway, uh, right, Mago berry…"

AN:

I'd already mostly dismantled I Choose You for parts, including completely stripping Cross of ever having had a Charmander, but Cross is Alolan.

They're off to a conjectured future PMD game where you can have a Litten or Rockruff as a partner (or significant NPC). In other fics I've predicted Volt Crash, living Pokédexes and psychic Raichu, so I may as well see if I'm right this time…