Morty, Raikou, and Fantina had all gone to the lecture hall to use the TM.
Only Cain was left in the training field, watching two Gastly battle each other. Of course, one of them was a transformed Ditto.
Hypnosis, Night Shade, Confuse Ray, Curse, Embargo, and Shadow Ball were the six moves that Gastly used the most. Shadow Ball had just been learned, and the effect of Embargo had not yet reached meastery. During battles, Gastly mostly relied on the combination of Night Shade, Hypnosis, and Confuse Ray.
However, Gastly should be like an assassin, requiring unexpected speed and lethal damage. Clearly, his Gastly had not achieved these qualities yet.
"Dodge and attack simultaneously with Shadow Ball."
Now, Cain's goal was to train Gastly's speed and the proficiency, power, and usage of Shadow Ball. All of this had to be done step by step. First, Gastly needed to become proficient with Shadow Ball to the point where it could be used instantly.
Next, Cain wanted to improve the concentration of Shadow Ball. Shadow Ball was a sphere of dark energy that dealt damage to the opponent by exploding when thrown. If the energy of Shadow Ball could be condensed into a shuttle shape, the damage would be even greater, based on the principle of "smaller force area, greater pressure."
Because Shadow Ball and Sludge Bomb both belonged to the category of explosive projectile moves, Cain had conducted many experiments in his previous life.
Cain had not yet let Gastly learn Sludge Bomb from the TM he held because the previously learned moves were not yet mastered. Learning too many moves at once could lead to biting off more than one could chew.
Another reason was Gastly itself. Although it had both Ghost and Poison types, the Ghost type dominated its body, while the Poison type was sealed and inactive. Currently, Sludge Bomb would likely have less than half the power of Shadow Ball in Gastly's hands.
So, Cain now needed to stimulate Gastly's Poison type attributes.
The same move would have vastly different effects on different Pokémon.
For example, Sludge Bomb, when used by the Drapion and Ariados Cain had raised in his previous life, had astonishingly powerful effects. The Sludge Bomb contained their own potent toxins, which became even more corrosive when they exploded, seeping into the opponent's flesh and causing guaranteed poisoning.
However, when used by regular Poison-type Pokémon, Sludge Bomb contained their own toxins, which increased the move's power but only caused moderate damage due to the less potent poison. To poison the opponent, the explosion had to break the skin, which was a far cry from the level of Cain's Drapion.
Some non-Poison-type Pokémon, like Parasect and Tangela, could also learn Sludge Bomb. In Cain's view, there was no need for such Pokémon to learn this move, as they lacked poison sacs and could only rely on gathering Poison-type energy, which wouldn't deal much damage, and the chance of poisoning the opponent was minuscule.
Gastly was quite unique, as it possessed the Poison type but was a gaseous Pokémon, unlike typical Poison types with poison sacs. However, its life composition contained a strand of poison nucleus, which wouldn't produce toxins unless activated.
So, most people only remembered Gastly as a Ghost type and didn't know about its Poison type.
Now, Cain's task was to stimulate Gastly's poison nucleus so that it could produce toxins, and this required the help of a Poison type Pokemon.
However, there were no Poison-type Pokémon in the Ecruteak Gym at all, and the group of Gastly present were useless.
It wasn't until Morty and the other two finished watching the TMs that they went to the training ground, and Cain was still pondering about the Gastly issue.
"Cain, why didn't you let Gastly learn the moves from the TM?" Morty asked.
"Not in the mood."
Cain continued to watch the fighting Gastly and Ditto while thinking.
At this point, Fantina became unhappy. "What kind of person are you? Morty is obviously concerned about you, and if you don't practice the moves from the TM, we won't be able to continue challenging the Brass Tower. Are you intentionally trying to hold us back?"
"Heh..." Cain sneered.
He wondered who was the one holding them back in the two attempts to challenge the Brass Tower.
Fantina was so angry at Cain's disdainful sneer that her face turned red, and she couldn't speak.
"If you want me not to hold you back, find me two pure Poison-type Pokémon." Cain said and then went towards Gastly.
"You, are you threatening us? Why should I find them for you? This person is too full of himself." Fantina complained in place.
Both Morty and Raikou knew Cain's character and knew that Fantina's complaints were in vain, so they went to practice on their own.
After two days, the trio's move practice had improved, but Cain still had no intention of using the TM.
In fact, Cain didn't need to be in a hurry to challenge the Brass Tower. He was planning to stay in the Ecruteak Gym for three years, and it had only been a month, still plenty of time to challenge the tower.
In these two days, he focused on Gastly's training the Embargo and Shadow Ball moves, and finally made good progress. Although Embargo was not as effective when used by non-Dark-type Pokémon, it could perfectly connect with Night Shade, which was the limit for a non-Dark-type Pokémon.
Shadow Ball had also reached the point of effortless mastery, but the training for a more condensed Shadow Ball had just begun.
Although Gastly could now learn Sludge Bomb, without stimulating the Poison type energy first, it couldn't unleash the true power of Sludge Bomb.
Even if the Poison Core was stimulated and activated later, the previously formed move usage would remain, and using Poison-type moves would not mobilize the toxins produced by the Poison Core.
The entire Poison Core would become a decoration, and the so-called Poison-type attribute would become a burden that was easily countered.
So he will need to active the Poison core first.
Gastly and Ditto were still attacking each other on the training ground.
However, Fantina couldn't sit still at this point, as she only had two months in the Ecruteak Gym.
"These are two Poison-type Swalot, I can only lend them to you for two days. My father just bought them for me from the black market."
Fantina said angrily, completely unwilling, even though it was a small expense for a Gym Leader, being led by the nose by Cain was almost unbearable for her.
"Thank you." Cain said as he took the two Poké Balls.
"Two pure Poison-type Pokémon have been lent to you, isn't it time for you to start learning the TM?" Fantina said.
"Don't worry."
After saying that, Cain left alone, not wanting them to see his upcoming training.
"Hmph, he's so annoying." Fantina pouted.
...
Cain came to a secluded area near the Brass Tower and released the two Swalot.
The special training to stimulate Gastly's poison sac was about to begin.