After reaching the Professional Level, Pokemon's rate of improvement generally slows down, and reaching the Gym Level requires significant talent; otherwise, the rate of improvement will drop to a standstill.
If Pokemon could improve every seven days slightly and every month greatly, the world would be full of Champions, and Elites would be as common as dogs.
Before reaching the Gym Level, levels can be reluctantly built up with time and effort, but beyond that, it greatly depends on intuition and talent unless a miracle-like chemical reaction of bonds between the Trainer and Pokemon occurs. Otherwise, Pokemon with poor talent will be stuck at the Gym Level.
However, Ash's Pikachu, while not of poor quality, is not particularly outstanding either.
Six A-grade talent, which is one in a million among Pikachu's kind, but still has some distance compared to Charizard and Gardevoir.
Ash is not sure why Pikachu's power is improving so quickly, but according to the experts in the group chat, Pikachu's improvement is actually considered normal.
It seems there is some secret in Pikachu that Ash has not noticed, but the experts in the group chat are not willing to tell him yet, only saying the time is not right.
Aside from Pikachu's enhancement, Charizard has reached the Professional Middle Level, and Gardevoir just reached the Professional Level a week ago. After reaching the Professional Level, the improvement of both Pokemon's speed has noticeably slowed down.
Only Pikachu continues to leave others in the dust.
Bulbasaur's power reached the Elite Junior Level earlier and has surpassed Wartortle, but after twenty days, it only reached the Elite Advanced Level, which was achieved a week ago.
Compared to before, the rate of level improvement has indeed been faster, but without evolution, this level increase is still somewhat slow.
The originally Advanced Peak Wartortle evolved into Blastoise during battles with Team Rocket and daily fights, closing the gap with Bulbasaur and reaching the Elite Junior Level.
Pidgeot's level has reached the Elite Peak, although Ash rarely uses Pidgeot in official battles, it often appears in wild battles.
And Pidgeot trains very hard itself, so it still outpaces both Bulbasaur and Blastoise.
Finally, there's Riolu, reaching the Advanced Middle Level in just about a month, directly spanning a major stage!
This is due not only to Riolu's relatively low level but also because of its strong talent and compatibility with Ash's Aura Power.
Every day, besides physical training, Riolu meditates on Aura with Ash, improving very quickly.
This is an exercise method other Pokemon cannot use; if other Pokemon could meditate on Aura with Ash like Riolu, their speed of improvement would likely increase.
In these twenty days, Ash also rotated the Pokemon from Oak's Research Institute, meeting Primeape, Butterfree, Tauros, and a thousand-year-old Gengar.
They are living quite well at Oak's Research Institute, and under Gengar's guidance, their power has not been slow to improve.
Gengar has taken on the duty of a Trainer in the backyard, and with Erika sending some perfume to Oak's Research Institute, the Pokemon there have auxiliary tools for training.
Compared to Ash's side, they lack the Power of Viridian, massage recovery, and dietary nutrition help.
However, Gengar's ability to train Pokemon is even stronger than Ash's... after all, being an old monster that has lived for a thousand years, it knows how to do everything!
Under Gengar's help, Butterfree reached the Elite Junior Level, a not-easily-achieved improvement for a Bug Type Pokemon.
Primeape also reached the Elite Junior Level and initially mastered some Ghost Type power, becoming quite adept at using Rage Fist.
According to Primeape, every time it uses Rage Fist, the Ghost Type energy within tries to fill its body.
Primeape has a premonition that if it lets the Ghost Type energy spread, it might never be able to evolve in this lifetime.
Regarding Primeape's situation, Ash asked the experts in the group chat, and they confirmed that Primeape's premonition is correct.
What Primeape needs to do is control the Ghost Type energy rather than be passively controlled by it. If the Ghost Type energy were to spread throughout its body, Primeape could still use Rage Fist but wouldn't be able to condense Ghost Type energy.
However, Primeape's difficulty in evolution surprised the group chat, as they said that in their world, Primeape's evolution isn't so troublesome, and fundamentally, there's no example of Primeape's evolution in Ash's world.
Ash's Primeape might become the first to evolve, and once it evolves, it will be remarkable, potentially receiving a gift from the world.
So, although evolution is challenging, the rewards are generous if Primeape perseveres.
Butterfree and Primeape have seen improvements, but Gengar... its level hasn't moved at all.
It has been stuck at the Elite Advanced Level for an unknown number of years; if it were that easy to improve from there, it would have reached the Champion Level long ago.