Gurrkin ended up with a list of Ash's thoughts about Pokémon and Mega Evolution which seemed to be relevant, to Ash anyway, and while Clemont said that they sounded helpful but more in a general life rules sense that didn't seem to dismay the Mega-Evolution Guru.

In fact, he said that it'd go well with his existing scroll of Mega Evolution advice, which was also more about general thoughts than anything.

That meant they'd taken long enough that the secret of the Tower of Mystery was revealed – there was a causeway to reach it which was only exposed at low tide.

"It depends what the time of the month is, how long it's exposed for," Korrina explained, walking through the sand alongside the causeway. "When tides are really minor, I think they're called neap tides, then it's only exposed for about half an hour, but when it's a spring tide it can be a lot longer."

"Really, the impressive bit is that this causeway never has too much sand on it," Lucario added, gliding along the causeway since it was his turn with the rollerblades. "It often seems like humans have developed amazing construction techniques with steel and concrete and glass, but missed how to do things like this with stone."

"I could ask Groudon if he knows, next time I see him," Ash suggested. "So, what are the rules for your challenge?"

"Well, I wanted to have a trainer-versus-trainer battle," Korrina said, as they began climbing the steps. "But I'm not a quick study in how to battle as Mienfoo, partly because I don't speak Mienfoo and the Mienfoo who's teaching me Mienfoo-fu has to use a blackboard a lot… actually, I'd kind of appreciate it if Lokoko would stick around for long enough I can get in a few good lessons. Anyway, I want to use Lucario, but apart from that… hmm, I'll say you need to use at least one Pokémon you caught in Kalos?"

"That sounds great!" Ash agreed. "And yeah, I think we can stay around for a day or so. I'm not sure where we're going after Shalour but I don't think we need to hurry."

"I don't think I've worked out how to use these to climb stairs yet," Lucario said, still at the bottom of the staircase.

"In case it matters, I'm using Lucario second," Korrina told Ash. "So, pick your first Pokémon!"

"I'd introduce him, but he kind of likes doing that himself," Ash replied, Pokéball at the ready.

Korrina nodded. "Then… Machoke, you first!"

Machoke posed, then noticed who his trainer was battling.

"Well, this should be interesting," he decided. "What Pokémon is Ash Ketchum going to send out against me?"

He cracked his knuckles.

In reply, Ash sent out Hawlucha.

"My name is Hawlucha," the Flying-type said, bowing, and adjusted his black face mask. "You may or may not have met my father. Prepare to fly."

"Let's go, Machoke!" Korrina called. "Begin with Low Sweep!"

Machoke darted forwards, using an arm for support, and twisted to swipe at Hawlucha's legs. The Flying-type jumped into the air, doing a somersault, and lashed out at Machoke with two rapid Wing Attacks in quick succession – one of which Machoke evaded entirely, but the other scored a hit.

"He's fast, but let's keep it up!" Korrina said. "Ice Punch!"

Machoke tapped his right fist with his left palm, then punched at Hawlucha, and missed so spectacularly that he staggered a few more steps before recovering.

"What just happened?" he said, whirling and pointing at where Hawlucha now was. "How did you do that?"

"I am not on your right-handed side," Hawlucha said, grandiosely, then jumped in and used Aerial Ace.

"Another Ice Punch!" Korrina called.

Machoke defended himself with both fists, taking on a boxer's defensive stance first and then augmenting that by punching one fist with the other to send out an explosion of ice, and Hawlucha was knocked backwards and did three flips before landing with a thump.

"Ow," he said.

"Hawlucha, it might be time to change styles!" Ash suggested.

Hawlucha sprang back to his feet, then pulled off his mask with a flourish.

Underneath was another mask, this time with stylized flames licking up it, and Hawlucha posed. "I am Hawlucha, the flame!"

"Is that legal?" Machoke asked.

"Well, if it isn't then that just means he's a Heel," Ash shrugged. "Is that the right term?"

"Hawlucha prefers the term rudo," Hawlucha clarified, then used Flame Charge.

"So, how does that actually work, then?" Gurrkin asked, which made Serena jump in surprise.

"I didn't realize you were there," she apologized. "I'd sort of mentally decided you were back in Shalour."

"Well, I've got a few tricks," Gurrkin replied. "And an Alakazam. A few tricks and an Alakazam, and Alakazam is very useful for the mysterious guru sort of thing. You should remember that."

"I'll do my best," Serena promised. "But I think it's sympathetic magic, also known as the Law of Imitation. It's one of the ideas that comes up a lot in magic, you see."

She pointed. "So Hawlucha's mask has flames on it, and that's associated with his current persona, which is Hawlucha… something?"

"The Flame," Fennekin contributed.

"Thanks!" Serena replied. "So it's associated with his current persona, Hawlucha: The Flame. Which is associated with… well, flames. And because of that, he can do things that are unique to that persona."

Gurrkin blinked a few times.

"I'll be honest, I wasn't expecting you to just tell me it was literal magic."

"Well, it could be something else," Serena admitted. "But I'm learning magic and so magic is the way I tend to think about these things… it could be a different type of magic, though. For example, another principle is the Principle of Contagion, which is that once two objects or people have come into contact a link remains between them that can be exploited or used in magic… for example, someone I met last week told me a lot about how Ash's friends May and Dawn both did their own kind of unusual things in Contests, and so did Brock from Pewter City a couple of times. So you could say the Principle of Contagion is involved there… or it could just be a coincidence."

She crouched down to let Fennekin jump onto her arm, then clamber up to her shoulder. "I'm hoping to get some much more concrete examples of magic spells going. There's one we've been working on which… hmm, do you think we should try?"

"I think we could give it a go!" Fennekin agreed.

Serena nodded, and took a feather out of her pocket. Fennekin blew on it, setting it alight, and it crumbled to ash and dust all at once in a single flare of incandescence.

Then she jumped off Serena's shoulder, wobbled a bit, and floated in the air.

"There we go!" Fennekin said. "It's a lot of work for something that I could do just by learning Fly, but it's the principle of the thing."

Then she dropped to the floor with a flumph and a muffled oof.

"We're still working on how long it lasts," Serena admitted, picking Fennekin up again.

"Aha!" Hawlucha declared. "Unfortunately for you, you have not merely trifled with Hawlucha: The Flame! You have also trifled with Hawlucha!"

He pulled off his flame mask, revealing that he was actually Hawlucha, and used Flying Press.

Machoke went whud into the ground. So did Hawlucha, for that matter.

"Well, Ash, that was an interesting battle!" Korrina said. "That Hawlucha of yours has some neat tricks… I should really see if I can get a Pokémon who's got that much variety. But now it's Lucario's turn!"

Lucario dropped from the ceiling and landed on the arena with a wham.

"We've worked on that a lot," Korrina added, as Lucario rose from his crouch and adjusted his Lucarionite armband. "It's a bit silly, but it's a great entrance!"

"Yeah, that kind of thing can be important," Ash agreed, and held up a Pokéball. "Your turn!"

Palkia came out.

"All right, Zoroark, we weren't going to be doing that anyway," Ash chided.

"You always know it's me," Zoroark sulked, transforming back. "But anyway, let's do this!"

"Yeah!" Ash agreed. "Here goes!"

"Well, if we're ready to start," Korrina said, raising her Mega Ring, and Lucario Mega-Evolved with a flash.

Zoroark didn't. He did something else.

Gurrkin leaned forwards. "What just happened to Ash's Zoroark?" he said. "That is Ash's Zoroark, right?"

"He's only got one, unless Aten evolved since last time I saw him," Serena replied. "And yeah, it first happened last week. We're still not sure what it is or what it should be called."

"But our working theory is: sympathetic magic again or something," Fennekin said. "It explains a surprising amount about the universe!"

"So, just to make sure I understand this?" Mega Lucario requested. "By transforming, I gained a power boost, longer fur, more spikes, and longer… whatever these are called."

He tapped the things which looked a bit like extra floppy ears but weren't.

"By contrast," he went on. "You have mostly changed colour?"

"Mostly, but that's not all," Zoroark replied. "I also have this swirly smoke stuff."

He waved his paw at it, demonstrating that it was fairly solid but also movable.

"This should be fun!" Korrina decided. "Begin! Lucario, Aura Sphere!"

"Let's go, Zoroark!" Ash declared. "Giratiny!"

Mega Lucario threw a blazing-fast Aura Sphere at Zoroark, who went poof and turned into Giratiny. The Aura Sphere tracked in unerringly, and passed right through the tiny replica Dragon-type.

"Huh?" Korrina asked, then winced as the Giratiny double spat flame and Mega Lucario divided most of it with his paws. "Try Dragon Pulse!"

That one did hit, knocking Zoroark out of his Illusion, but he backflipped and landed before conjuring an illusory Sacred Sword out of the air.

Mega Lucario matched him by forming a Bone Rush, then glanced back at Korrina for approval.

"Yeah, good plan!" Korrina agreed. "And try and hit him with a Power-Up Punch if you get the chance!"

"Night Daze!" Ash called.

Zoroark threw a ball of dark sparkles at Mega Lucario, ducked under the first Bone Rush, blocked the second with his fake-Sacred Sword (which smashed the Sword but blunted the attack), then turned briefly into Noctowl when Mega Lucario swung a two-handed Bone Sword attack at him.

The attack hit his Noctowl-face with a whunnnng and made Mega Lucario bounce into the air from recoil, but troubled Zorowlark not a bit.

"I'm starting to get annoyed," Mega Lucario said. "Also tired. What on earth is that you're doing? It's not Transform, I can tell."

"That's right, all right," Zoroark replied. "As far as we think at the moment, my Illusions are just a tiny bit more real than normal… specifically, they copy immunities."

He flicked his mane, then looked a little annoyed. "I can't really wag this the same way I could a tail… anyway, the rest of it is just that there's a lot of ways that some Pokémon are immune to some moves."

"Ah, I see," Mega Lucario decided. "Yes, I think finding that annoying is the correct response. I'm glad we could clear that up."

He stamped on the ground. "Stone Edge!"

Ash pointed. "Zoroark, above you!"

Zoroark looked up, made a yipe sound, and dodged out of the way just before one of the ceiling slabs came down on top of where he'd been standing.

"Lucario, careful!" Korrina reminded him.

"I actually didn't mean to do that," Mega Lucario winced. "I was going for a rock to come up… anyway-"

A paw tapped him on the shoulder, then Zoroark used Foul Play.

"Take that," the Dark-type added, unnecessarily, then ducked as Mega Lucario sprang up from the floor with a powerful Blaze Kick. "Oh, okay, maybe I'm not done just yet – fine, let's try this! I haven't done it yet since evolving so this should be pretty interesting!"

There was a moment of blurred intensity when Mega Lucario was using Counter to fend off the charge of a suddenly-there Dynamaxed Zamazenta, which ended with Zoroark fending off a headache in the middle of a crater in the floor and Mega Lucario muttering something about deja vu upside down and about a foot deep in the wall.

Then there was a flash of golden light in mid-air, and Starly came through.

"Good, evening?" he said. "I think it's evening. Anyway, I heard you were battling someone with a Lucario… am I early enough to be the one who battles Lucario? I got a lift from Unown as soon as I heard."

"Uh… you might be a bit late," Ash admitted. "If you want to challenge Korrina's Lucario, anyway."

"Yeah, Ash has already won the badge, because I don't think Lucario can keep going after that," Korrina agreed.

Then another Lucario went slam into the ground in front of them.

"I admire your spirit," the Steel-type said. "I am also a Lucario who once battled in this gym, and I would like for my trainer to let me battle you, even if it is not as part of the Rumble Badge challenge."

"Hmm," Ash frowned. "I guess you must be Gurrkin's Lucario, then? Do you want a replacement Lucarionite? I'm pretty sure I can get you one from Phanpy, or from Diancie…"

"If that Lucario gets a Lucarionite, then it's only fair if I get one as well," Starly said.

There was a whud as Korrina's Lucario finally peeled off the wall.

AN:

Starly will be handled in extra time, i.e. the next chapter.