The group of pokemon he found are feebas. They are deem as most ugliest pokemon known in the world.
Feebas are pokemon that people mostly ignore because they don't know the value of it. They have no value in the market is due to the reason because very few people know that they have another evolve form and fewer know how to evolve it. Jack is one of the few who knows those things.
Their evolved form is the most beautiful pokemon in the world, Milotic. They have both strength and elegance and are useful in many ways. But still Jack hesitate for a moment before deciding to go there. It is because just like Magikarp not all feebas can evolve into Milotic and their evolution process is even harder. They need to have enough beauty and confident plus have good aptitude to evolve into Milotic. That is why they are even rarer than pseudo legendaries. They are also very strong, as strong as Gyarados and if Jack has to choose between the two, he would choose Milotic because they are mild and much easier to train. Also not many people know this but their dragon bloodline is as rich as Gyarados. Although Milotic can't learn outrage, but they have dragon type hereditary abilities which Gyarados does not have.
(Author Note: hereditary abilities are egg moves in games except for a fews)
"Unless I found a feebas of at least light blue aptitude I will ignore it." Jack thought while going there. The another problem is it is incredibly hard to train feebas as before level 15, they only know one move Splash which is useless. But he found one with light blue he is confident to make it evolve into beauty Milotic. Although the process is hard he knows the right item to help it evolve into it, which is Prism Scale. It is an luxury item with no other use than being beautiful so only rich girls like it.
Strangely enough when Jack arrived at the where feebas are, he found out that they have very high aptitude than normal pokemons. Many of them are green aptitude and some are even deep green. Still even deep green feebas are not valuable in the market so Jack ignores it. After searching for a while, Jack found something in a bush not far from him.
After checking it, it is a same fin but normal feebas fin is of blue color while this one is grey. Seeing this Jack thought about the most likely possibilities and run towards it to check its aptitude. Without his eyesight it is difficult to see this distance. After rushing to where it is, Jack saw a purple feebas. Jack held his excitement and check information of this pokemon.
Pokemon: Shiny Feebas (light blue)
Gender: Female
Level: 7
Attribute: Water
Characteristic: Swift swim
Holding items: None
Hereditary Abilities: Dragon Dance, Dragon breath, Dragon pulse
Basic Abilities: Splash
TM: None
"Holy shit!!, this is a shiny feebas. And what the fuck are these hereditary abilities. All of them of dragon types. It even has a dragon dance. I AM RICH!!" Jack shouted in excitement while hugging the feebas. Feebas is a timid pokemon so other than being confused, she gives no other reaction when receiving sudden hug from a strange human.
Jack is very happy to find out that the dragon bloodline in this feebas is even richer than some dragon types pokemons. Although she can't use them before evolving into Milotic he is still very satisfied. Seeing these Jack catches her immediately without wasting any more time. Even in his previous life, he has not met many shiny pokemons but in this island he manages to catch two of them and both have light blue aptitudes.
This tell him that this island is much more mysterious than it seems. Team rocket has their respective islands to train each levels and this island is to train executive potential trainers. Even so, the aptitudes should not be this great which means this island still have secrets that even team rocket is not aware off. Thinking about it makes Jack wants to explore more but he needs to return first to take part in second trial, so he decided to go back first.
Due to the heavy rain, he does not face many pokemons on the way. Pokemon like spearow groups beedrill, are all very uncomfortable in rain so even after the rain stops, Jack does not face much and safely pass through those pokemons territories. Of course, he only passes them through the border line and does not dare venture deep.
There is still a day left for 2nd trial so Jack thinks about how to train Feebas on his way. Feebas needs another 8 levels to fight and only after reaching level 15, she would learn tackle and will be able to fight. So Jack needs to train her physical first. Luckily her characteristic is swift swim. It means it raises speed in water and rain. So it is better for her to train in speed before evolving into Milotic.
There is one problem tho. Although Feebas can live in the air because she is a pokemon, she still needs to be in water to move and train. So Jack have to go to water sources which are very dangerous from now on in order to train.
When Jack arrive team rocket headquarters, the first thing he does is to sell the pokemons so he goes to the store and meet the shopkeeper. There are currently 20 pokemons on him which he needs to sell. As for whether he will get suspicious for selling only good aptitude pokemons, he does not need to care about it anymore because if he place first in tomorrow, he will get attention of higher level members. They strictly forbid other team rocket members to act against participants other than participants themselves.
After selling all 20 pokemons plus the remaining points, Jack now have the total of 220,000 points which makes the shopkeeper drop his mouth. Among the pokemons he sell, the highest price is the not deep green but the light green nidoran with sheer force characteristic. The price is this pokemon is 30,000 the same as normal light blue weedle. Ignoring the suspicious gaze of shopkeeper Jack continues to look for which TMs to buy.
Right now feebas has the characteristic of swift swim, so after evolving into Milotic it will change into Marvel Scale which is a very powerful characteristic. After thinking a while Jack decided to buy TMs which compliment this characteristic.