Morty, Raine, and Fantina had all gone to the lecture hall to use their TM discs.
Only Tetsuya remained at the training grounds, watching two Gastly fighting each other. Of course, one of them was Ditto.
Hypnosis, Night Shade, Confuse Ray, Curse, Embargo, and Shadow Ball were currently the six moves Gastly used the most. It had only just learned Shadow Ball, and Embargo hadn't reached optimal effectiveness yet. In battle, it still mostly relied on the combination of Night Shade with Hypnosis and Confuse Ray.
But Gastly was an "assassin". What it needed was unexpected speed and deadly, one-hit damage. Clearly, it hadn't reached that standard yet.
"Shadow Ball while dodging."
Tetsuya's goal now was to train Gastly's speed, as well as its proficiency and power in using Shadow Ball. These things could only improve step by step. For now, the priority was getting Shadow Ball to the point where it could be used reflexively.
After that, it would be about perfecting the Shadow Ball. The move was essentially a black sphere of energy thrown to explode and damage the opponent. If Gastly could condense the energy into a spindle shape, based on the principle of "smaller impact area, higher pressure," the damage on impact would be even greater.
Since both Shadow Ball and Sludge Bomb were projectile explosion-type moves, Tetsuya had conducted many experiments on this aspect in his previous life.
The reason he still hadn't had Gastly learn the TM Sludge Bomb, even though he had the disc in hand, was twofold. First, Gastly hadn't yet mastered its existing moves. Piling on too many at once would lead to the cliche "jack-of-all-trades, master of none".
Second was Gastly itself. Despite being a Ghost/Poison-type Pokémon, its Ghost side clearly dominated its body composition. The Poison type was completely "dormant". At this point, Sludge Bomb in Gastly's hands(?) likely wouldn't even match half the power of Shadow Ball.
So now he needed to stimulate Gastly's Poison type.
The same move could produce drastically different results depending on the Pokémon using it.
Take Sludge Bomb, for instance. In his previous life, the move in the hands of his [Badly Poison Drapion] and [Badly Poison Ariados] could only be described as devastating. By infusing their own toxic poison into the Sludge Bomb, the explosion became a corrosive force that tore into the opponent's body and seeped into their flesh. Poisoning was guaranteed… 100%!
Ordinary Poison-type Pokémon using Sludge Bomb relied on their own Poison Glands to store poison. When they used the move, some of their "toxin" would blend into the attack, boosting its power.
But since the poison wasn't especially potent, it would only cause minor damage. Poisoning the opponent depended on whether the explosion was strong enough to tear the skin and let the poison in. That was a far cry from his Drapion's level.
Then there were Pokémon like Parasect and Tangela, who weren't even Poison-types but could still learn Sludge Bomb. From Tetsuya's perspective, such Pokémon had no business learning the move.
Without a Poison Gland of their own, they could only rely on gathering Poison-type energy to use it. The attack had little power and virtually no chance of poisoning the opponent.
Gastly was a bizarre case. It had Poison typing, but being a gas-based Pokémon, it didn't have a "Poison Gland" like typical Poison-types. However, a strand of "Poison Core" did exist in its life structure. Unless stimulated, though, it wouldn't generate any poisonous toxins.
That's why most people only remembered Gastly as a Ghost-type and never realized it was also part Poison.
So now what Tetsuya needed to do was stimulate Gastly's Poison Core to generate poisonous toxins. And for that, he would need Poison-type Pokémon.
But there weren't any Poison-types at Ecruteak Gym right now. The group of Gastly they had were useless for this.
---◓---
Even when Morty, Raine, and Fantina returned from watching their TM discs and arrived at the training grounds, Tetsuya was still troubled over Gastly's issue.
"Tetsuya, why didn't you have Gastly learn any of the TM moves?" Morty asked.
"Not in the mood."
Tetsuya kept watching the fight between Gastly and Ditto, deep in thought.
At that moment, Fantina got annoyed. "…Pardon? What's your problem? Morty was clearly just being considerate. Besides, if you don't train using the TM moves, we won't be able to keep challenging the tower. Are you trying to drag us down on purpose!?"
"Heh..." Tetsuya let out a cold laugh.
He wondered who exactly had been dragging the team down in those last two attempts.
Fantina's face turned bright red with frustration at Tetsuya's dismissive smirk. She couldn't even get a word out.
"If you don't want me to 'drag you down', then get me two pure Poison-type Pokémon," Tetsuya said before walking off toward Gastly.
"You…! Are you threatening us? Why should I get them for you?! This guy really thinks he's something," Fantina grumbled on the spot.
Morty and Raine, already familiar with Tetsuya's personality, knew arguing with Fantina would be pointless. They each returned to their own training.
Two days passed. Morty, Raine, and Fantina had all made visible progress with their move training. But Tetsuya still hadn't touched the TM.
Truthfully, Tetsuya wasn't in any rush to challenge Brass Tower. He planned to remain "hidden" inside Ecruteak Gym for three years. It had only been a month, there was plenty of time.
These past two days, he had focused on training Gastly's Embargo and Shadow Ball. The progress had been solid.
While Embargo didn't have the same effectiveness in Gastly's hands as it would for a Dark-type Pokémon, it had reached the point where it could seamlessly connect with Night Shade. That was likely the best a non-Dark-type Pokémon could hope for.
Shadow Ball had also reached a stage where it could be unleashed freely, but the training to condense it into a spindle form had only just begun.
Even though Gastly could now learn Sludge Bomb, it would never unleash the move's full potential.
And even if the Poison Core were stimulated later on, if Gastly had already formed a fixed way of using the move, it still wouldn't incorporate the newly generated poison.
The entire Poison Core would become useless, its Poison typing reduced to a burden, nothing more than a type disadvantage waiting to be exploited…
Gastly and Ditto were still battling in the training grounds.
But by now, Fantina had completely lost her patience. After all, she only had two months to stay at Ecruteak Gym.
"These are two Poison-type Swalot… You can borrow them for two days. My dad just bought them for me from the market!" She said furiously.
Fantina was clearly unhappy. Though it was only a small expense for a Gym Leader, the feeling of being led around by Tetsuya was unbearable.
"Thanks," Tetsuya said as he took the two Poké Balls.
"Now can you finally go learn your TM?" Fantina asked.
"Oh… Don't worry."
Tetsuya walked off alone. He didn't want them to see what he was about to do next.
"Hmph, he makes me so mad…" Fantina muttered with a pout.
---◓---
Tetsuya arrived near the secluded area by Bell Tower and released the two Swalot.
The special training to stimulate Gastly's Poison Core was about to begin.