Mega Evolution transcended the limits of conventional Pokémon Evolution, allowing certain Pokémon to temporarily assume a more powerful form and unleash hidden abilities that ordinary evolution could never grant.
To trigger Mega Evolution, the Trainer needed to carry a Key Stone, which would resonate with the corresponding Mega Stone held by the Pokémon.
On the way to the Seven Islands, Caster had already obtained a Gyaradosite after catching a Gyarados while fishing.
In other words, as long as he obtained a Key Stone, Caster could try to Mega Evolve his Gyarados.
However, as far as Caster knew, Key Stones were not exactly common.
This was especially true at this point in time, when Professor Augustine Sycamore's research had not yet been published and only a handful of people knew about or paid attention to Mega Evolution.
As a result, the vast majority of people had no idea that Key Stones and Mega Stones even existed, let alone what they could do, and simply regarded them as ordinary gemstones, leaving these treasures to gather dust, unrecognized.
According to Caster's original plan, after competing in the Indigo Conference, he might consider traveling to the Hoenn region.
One reason was that several Pokémon native to Hoenn would fit perfectly into his Rain Team, so of course Caster couldn't pass up the chance.
Beyond that, Caster wanted to try his luck and see if he could get in touch with Steven Stone, hoping to obtain a Key Stone and other Mega Stones from him.
Steven was famously obsessed with rocks and stones.
For the sake of digging up stones, Steven couldn't even be bothered to remain Champion.
He liked to spend his days mining and collecting rare stones at places like Meteor Falls, so he should have a Key Stone on hand.
In return, Caster could share information about Mega Evolution with Steven and even help his Shiny Metagross Mega Evolve ahead of schedule.
Of course, it would be even better if the two of them became good friends in the process.
After all, who could turn down a handsome, wealthy, and generous friend?
Yet now, completely unexpectedly, a Key Stone had appeared right before his eyes, gleaming and unmistakable, catching Caster entirely off guard.
Caster's breathing quickened as he picked up the pendant from the shelf with trembling hands, examining it carefully and turning it over again and again.
"It really is a Key Stone!"
Once he confirmed it wasn't a fake, Caster's face lit up with wild joy. "Mr. Albert," he said firmly, "I choose this item."
"Huh? Why?" Albert asked with a puzzled look. "Caster, is there something special about this pendant?"
This pendant had been sitting in the treasury since Albert was young. No one knew where it came from, and no one knew what it did.
It had simply always been there, so generation after generation of Trainer Tower caretakers had never bothered to clear it out, and it had remained there as mere decoration.
After all, it was just a pendant and didn't take up much space.
Yet now, of all things, Caster had picked it out at first glance.
As an Elite Trainer, Albert had sharp powers of observation, and judging by Caster's reaction, he was fairly certain the item had to have some kind of special function.
"I think I've seen the pattern inside this pendant's gemstone somewhere, in an old text," Caster said, thinking it over for a moment, his answer a half-truth and a half-lie.
"According to that text, it might hold some kind of mysterious power. I'd like to take it and study it. There might be a major discovery in it."
At this point in time, Mega Evolution was virtually unknown in both the Pokémon research world and the battling world, and Caster didn't want to draw too much attention to himself in case he let something slip and brought trouble upon himself.
But at the same time, he didn't really want to deceive Albert either, so he could only answer with half-truths, confirming the Key Stone's value without revealing exactly what it did.
"I really didn't expect you to have a talent for research too."
Albert laughed, not taking Caster's words too seriously, and instead said warmly, "That pendant has sat there unwanted for decades. Since you want to research it, I might as well do you a favor and just give it to you."
When Caster heard this, his eyes went wide. "Mr. Albert, what do you mean by that?" he asked, not quite sure he'd heard right.
"I mean exactly what I said. That pendant's been sitting uselessly in the treasury, gathering dust for decades. I might as well just give it to you. I hope you figure out what it does soon."
Albert added generously, "Besides that, you can still pick one more item as your reward."
Caster was overjoyed to hear this and thanked him. "Mr. Albert, thank you so much. I'll consider this a favor I owe you."
The Key Stone was what Caster had wanted, but the King's Rock was something he'd wanted too.
If he'd had to choose only one, Caster would have picked the Key Stone, since Key Stones were practically impossible to find anywhere on the market.
But now that he could get both items at once, saving himself who knew how much trouble, he was naturally delighted.
Caster's talent and potential went without saying. To have this level of strength so early in his journey meant his future was bound to be limitless.
Getting Caster to owe him a favor felt like a good deal to Albert too, and both of them walked away satisfied.
And so, Caster tucked the Key Stone and the King's Rock into his bag together, and the two of them left the treasury in high spirits, chatting happily the whole way.
With Albert leading the way, Caster first went down to the first floor, then let out all his Pokémon for a group photo.
"Come to think of it, we've never taken a big group photo together!"
Looking at the Pokémon under his care, Caster felt a rush of emotion.
Glancing at the many Pokémon gathered around him, Caster smoothed down his clothes, then flashed a grin, trying his best to look bright and cheerful.
"Grrrowl~"
The fierce, domineering Gyarados stood directly behind Caster with its head raised high, jaws wide open and eyes glaring.
It was Caster's best partner and his ace Pokémon.
"Pika~"
The soft, adorable Pikachu perched on Caster's shoulder. Even though it held up both paws in a peace sign, its face was puffed up in a sulk.
It hadn't gotten to battle at all during this match, from start to finish, so naturally it wasn't happy.
"Dra~"
The newly evolved Dragonair coiled up on Caster's left side, its eyes sparkling and the single horn on its head gleaming brilliantly in the sunlight.
Slowpoke and Shellder stood side by side on Caster's right.
"Sloooow~"
Slowpoke opened its mouth in a yawn, but out of the corner of its eye, it glanced at Shellder beside it, its gaze full of disdain.
"Shell~"
Under Slowpoke's disdainful gaze, Shellder sneaked closer to Slowpoke's tail, its big pink tongue hanging out as it practically drooled. It looked every bit like a besotted fool trailing after Slowpoke.
It desperately wanted to lick her, but without Slowpoke's permission, it didn't dare act rashly, afraid of getting smacked for it.
Click!
The image froze in place, and just like that, the first group photo of Caster and his Pokémon came into being.
The photograph would hang in the Trainer Tower's main hall as proof of Caster's victory, where every future challenger could see it.