In order to find out the reason behind the MEGA Evolution riot, Champion Ash returned to Lumiose City after a long absence, only to find that the city had completely changed.
An event called ZA Ascension Battle was being held in Lumiose City, and anyone who could reach the highest A-Level would not only earn the title of Lumiose's strongest Trainer but also receive unconditional assistance from the organizers to fulfill a condition, even if it meant becoming the ruler of Lumiose City.
Champion Ash keenly sensed something amiss within, so he disguised his name and appearance to enter the ZA Ascension Battle. As expected, he became the most powerful Trainer in the competition and met the organizer of the event.
In front of the chairman of Star Company, Champion Ash revealed his true identity and asked about the Ascension Battle in Lumiose City and what was happening with those out-of-control Mega-Evolving Pokemon.
Finally, he learned the truth from a man named AZ. It turned out that the leader of Flare had previously activated the Ultimate Weapon, causing an anomaly in the guardian device inside the Prism Tower.
Initially, the situation was still within a controllable range, but recently many Pokemon in Lumiose City had started to become afflicted. Many berserk Pokemon even actively attacked humans, while some mysteriously carried MEGA Evolution Stones and were exposed to the energy emitted by the device, enabling them to MEGA Evolve without a Trainer.
However, this type of MEGA Evolution would make the Pokemon lose their sanity, rendering the energy uncontrollable.
The entire Lumiose City was thrown into chaos.
Finally, AZ and Star Company came up with a plan: to select the strongest Trainer and send them inside the Prism Tower to stop the guardian device.
To stop the device, they needed a Pokemon beside AZ—a Floette, which had survived for three thousand years.
Only a powerful Trainer could command the ancient Floette and have it perform MEGA Evolution to stop the guardian device.
This responsibility ultimately fell on Champion Ash's shoulders, and he successfully resolved the Prism Tower situation.
However, he didn't rely on Floette but rather on Greninja and Zygarde's power.
[Advanced Ash: Greninja is a Pokemon from the Kalos Region, right? Zygarde is the guardian deity of world ecology. Can these two Pokemon cooperate?]
Since Champion Ash only provided a brief overview, Ash didn't know the specifics. He found it strange when hearing about Greninja and Zygarde working together.
It was as if you said having Fearow and Ho-Oh cooperate to resolve a world crisis. It was just too odd!
[Champion Ash: My Greninja is a little different. It's not just me, all 'Ash' are like this. Even you, newcomer, one day you'll meet your destined Froakie, and then you'll understand what I mean.]
Champion Ash only mentioned it briefly, thinking that saying too much might affect fate itself, so he didn't intend to disclose Greninja's special abilities to Ash and continued speaking.
After resolving the Prism Tower incident, Lumiose City's disturbances hadn't ended.
Special alternate spaces appeared around Lumiose City, resembling a grayish version of the city filled with Pokemon from various regions.
Moreover, over time, the area of alternate Lumiose grew larger as real Lumiose was gradually being devoured.
Thus, Champion Ash reached out to Hoopa, trying to understand some patterns of alternate space's appearance, and eventually identified the mastermind—Darkrai!
That Darkrai absorbed the excess energy emitted by the device, resulting in its uncontrolled MEGA Evolution.
Utilizing the nightmare abilities, it projected the dream world into reality, leading Lumiose City to be swallowed by dreams.
When Champion Ash defeated Darkrai, the disturbances in Lumiose City finally came to an end.
Though the disturbances ended, the appearance of alternate space led to more MEGA-Evolving Pokemon being discovered. However, those MEGA-Evolving Pokemon found inside the alternate spaces weren't able to MEGA evolve in the real world.
Ultimately, Champion Ash discovered the reason.
It was because the Gene Chain within those Pokemon hadn't been activated, making them unable to resonate with MEGA Evolution Stones and, thus, unable to MEGA evolve.
The principle behind Otherworld Lumiose City lay in nightmares filled with the fantasies of Lumiose City's residents.
Thus, some Pokemon's gene chains inadvertently got activated in the dream world, enabling them to MEGA evolve within Otherworld Lumiose.
Lucario's alternate evolution form was such a case.
But if your Lucario hadn't entered Otherworld Lumiose, then it wouldn't be possible to rely on dream power to activate the hidden gene chain, resulting in Lucario's inability to utilize another Evolution Stone to evolve.
[Advanced Ash: So, does this mean if I want Lucario to evolve into another MEGA form, I have to find Darkrai first?]
[Champion Ash: That's just one of the ways. Now that you know the reason, why don't you try using your miraculous Aura Power to see if it can be activated?]
Dream activation was just one of the methods. For others, unless they replicated Champion Ash's accomplishments, there was really no way to activate a Pokemon's gene chain.
After all, this thing involves Pokemon genetics, and generally, only researchers can think of a way, so Trainers may as well forget it, as it's not something that can be activated just through training.
But Ash is different; he possesses Aura Power. It's described as Aura Power but reads like Omnipotent Power, applicable in all situations.
Even for something like activating a gene chain, it might be possible to unlock it with Aura Power.
If Aura Power proves ineffective, then either consult Professor Oak or find Nightmare God.
[Advanced Ash: I understand, thank you, Champion!]
...
In reality, Ash returned to his senses, opening his eyes while processing what Champion Ash had said.
Apart from Lucario's other gene chain, one thing deeply concerned him—Froakie.
Although Champion Ash didn't elaborate, Ash's intuition told him that Froakie's existence was significant for him!
However, he currently didn't have the time to travel to the Kalos Region, and meeting Froakie seemed far off, so he decided to put this matter aside for now.
"Pika Pika~" Pikachu nudged Ash, pointing forward. Ash followed Pikachu's direction and saw an old man with white hair walking toward them confidently.
This should be Mr. Kurt. His age seemed even older than Gurkinn's, but his energy didn't lose out to young people.
Are all elderly people now filled with such vitality?
"Hello, are you the youngsters Professor Oak mentioned?"
"Yes, I'm Ash, and these are my partners Misty, Brock, and Serena."
Kurt nodded at them and then focused on Ash: "I know you. Oak really found a good seedling. It seems the pillar of Kanto won't take long to arrive."
"Let me see that Pokeball."
"Alright." Ash handed the GS Ball over to Kurt from his backpack.
Having the GS Ball in hand, Kurt fiddled with it for a moment and then exclaimed in amazement: "I really don't know who crafted this Pokeball. Its functions aside, just the craftsmanship is enough to startle my old bones."
"I need some time to study this Pokeball. Chiharu, take them to the back mountain for a stroll. If you can collect some Round Apricorns, I can make some Apricorn Balls for you."