"Dear Axel,
My gift for you is personal. There are 5 notebooks that I have hand-written by myself. It is my personal experience on how to raise a strong Pokemon.
There are some general things that you would already be aware of. There is also my personal insight on how to properly raise your Pokemon.
Remember, I don't want you to follow all the advice in the notebook to the letter. If you did that, you would just be a second me. What I want you is to be aware of the mistakes that I made and hoped that I would have known about them in the past.
Just go through those notebooks and make your own history.
Your Gym leader
Giovanni."
This was written in the letter. Giovanni had given him a treasure. Getting an insight into Pokemon from the gym leader was a huge thing. Nobody would want to give such information. Imagine you worked your ass off all your life to reach the stage of the gym leader. Would you really give all your secrets to another person?
Of course not.
Even Oak had not given him the information of his secret for raising his Pokemon.
'So, why would Giovanni do it? Is this some sort of trap? Did he want to recruit me in Team Rocket in the future?', Axel's thoughts started to move around.
He first thought that it was shady but then he crossed it off. The Giovanni he met today was a genuine guy. He really wanted to help Axel. So, Axel thought to accept the gift.
'I guess I owe him now.', he thought.
He took out a notebook and started to read.
###
After 2 days,
He had finished the first notebook. The first notebook was titled 'Abilities and hidden abilities' and boy did it blow his mind. The notebook was not thick. It was only 50 pages long. It was not detailed with all the numbers and statistics but filled with his personal experiences as said in the letter.
It took him 2 days cause he wanted to read it and re-read it all over again and get it inside his head. He realized that he had not given importance to Pokemon abilities and hidden abilities. He had read the general things found on the internet and taught to him in school but they never focused much on abilities and hidden abilities.
As per Giovanni, abilities and hidden abilities were to be taken seriously. When a Pokemon was about to reach King rank, they had to fulfill a lot of requirements. One of them was to have sufficient mastery of the abilities and hidden abilities. The keyword was 'sufficient', not fully mastered.
Axel knew about this. Looking at the mastery percentage of abilities and hidden abilities of his Pokemons, he was satisfied.
The book also said that the Pokemon could use their abilities and hidden abilities much more smoother when they evolve and rank up. When a Pokemon evolves and ranks up, they come closer to their primal self. Abilities and hidden abilities are a part of their primal self.
Axel knew about this too. Not the primal part but he had noticed a rise in percentage in the abilities and hidden abilities when they evolve or rank up.
However, as per Giovanni, after reaching a certain stage in abilities and hidden abilities training, Pokemon could not increase their mastery until they evolve or rank up. This was concerning for Axel. Suppose, if he was to train Ivysaur's ability 'Overgrow' to its maximum potential and let it evolve, what would happen? Others may not know the exact level to which Ivysaur to raise its mastery on 'Overgrow' but he can due to the system.
He wanted to try it.
The book also said that when a Pokemon reaches King ranked stage, it would increase/or evolve its ability and when it reaches the champion rank, it would increase/or evolve its hidden abilities. Axel knew about that. Elder Adam had demonstrated it to him.
However, what he didn't know was that the type and level of increase or evolution would depend on the Pokemon itself. If a Pokemon had trained their abilities and hidden abilities diligently, they would have greater success when they reach King ranked and Champion rank.
This blew Axel's mind. He regretted not focusing his training on the abilities of the Pokemon. This was not general knowledge but the experience of a gym leader. It was very rare to see a trainer with a Pokemon of King ranked or above. Those who had such level of Pokemons would not reveal their secrets. He thought to focus on abilities from tomorrow.
There was another interesting fact. Giovanni said that the Pokemon whose abilities and hidden abilities change after their evolutions should have some significance. After evolution, some abilities would have a completely different effect. For example, Nidorino hidden ability is 'Hustle'. It would change to 'Sheer Force' when it evolves to Nidoking. Giovanni believes that even if the abilities and hidden abilities change after the evolution, the former abilties/ hidden abilities should be mastered well. He didn't know the exact effect of it but hypothesized that it would be beneficial.
He also hyothesized that 'Hidden ability' were completely different than 'ability'. He said that it may have a totally different effect after the Pokemon increases/ or evolve its hidden ability when it reaches Champion rank. However, since he didn't have a champion ranked Pokemon, he could not tell.
There were other hypotheses of abilities and hidden abilities that had been mentioned in the notebook. He thought to experiment with it in the future.