Oliva, Galar Fire and Laplace from the Six Heroes come out of their balls on the Brave Asagi's Wing Deck! Liko decides to test her strength against Oliva, Roy against Galar Fire and Dot against Laplace!!

The Rising Volt Tacklers have all come to the Land of Kitakami to meet with Terapagos researcher Briar. The land is currently in the middle of a harvest festival that the group end up taking part in, where Friede takes great interest in the Yabasocha belonging to Seille, a girl he meets there. Meanwhile, Roy and Achigator accidentally touch a machine set up at a stall, which causes them to switch bodies...?!

After hearing that Briar is at Terasu Pool, Liko and the others start climbing Oni Mountain. On the way, Kanuchan is overjoyed to spot some nice iron, and starts pounding it with its hammer. Dot is overwhelmed with emotions from seeing Kanuchan's hammer grow in size so suddenly... but then a wild Otoshidori shows up and takes Kanuchan's iron.

As Liko and the others reach Terasu Pool, they locate Briar, who becomes extremely excited when she sees the Terapagos Liko has with her!! When they ask Briar about Terapagos, she takes out the Scarlet Book and starts explaining to them how it concerns the adventures of her ancestor Heather in Area Zero of the Great Crater of Paldea...

Sazare, who Liko and the others met in the Land of Kitakami, had taken a photo; A photo of a Basagiri! After learning this photo was taken on Mt. Tengu, they join Sazare in searching for the Basagiri there. However, they all end up getting separated after an attack by wild Pokémon... Will they be able to find the Basagiri from the Six Heroes?!

The Basagiri from the Six Heroes finally shows itself! Not only that, but Laplace leaps out of its ancient monster ball as well. Just what is the relationship between these two...?! Basagiri acts as if it wants to test Liko and the others' strength, so Liko, Roy and Dot challenge it to a battle!! Will their efforts be able to make an impact against Basagiri's finely honed moves?!

Liko's grandmother Diana has returned to the ship, and Liko ends up having to battle her and Windie in order for Diana to ascertain how much Liko has grown...?! Diana also tells the group about a secret of Lucius' that she gained knowledge about while traveling the world... one that involves the connection between Lucius and the Explorers, as well as the three adventurers that founded the Explorers...!

On their second visit to Terasu Pool, Liko and the others meet Rystal, who tells them about the adventures of the former Explorers. How did this trio that once journeyed towards the paradise Rakua meet, and what did they see when they arrived there? The details surrounding an unknown adventure that took place a hundred years ago will now transcend vast time and finally be revealed!!

Friede suggests Liko and the others meet with someone named Sohdayo who can help them locate Entei. When they land on the savannah, they're immediately attacked by Rikikirin... but just then, Sohdayo suddenly shows up. He introduces himself as a "truthful Pokémon journalist"... and is actually a former member of the Rising Volt Tacklers?!

While visiting Randou's hometown Asagi City, Liko and the others meet the fishing boat rental operator Mamoru, a passionate fan of Kinjiro, a movie star of yesteryear. Mamoru tells them about his enthusiasm for the "VS Samehader" movie series Kinjiro starred in.

An eyewitness report has led the Rising Volt Tacklers to conclude that Entei, which is highly related to volcanic activity, is likely to appear near an undersea volcano, and take turns lying in wait for it there. And then one night, Entei appears with a loud roar, challenging Liko and the others to a battle in order to test them!

Liko and the others return to the Paldea region in search for more information on Entei, and go see Pokémon League chairwoman Omodaka to get permission to enter Area Zero of the Great Crater of Paldea. However, the condition Omodaka sets is that they need to win a Pokémon battle against her...?! It's time for Liko, Roy and Dot VS Omodaka! How will Liko and the others take on the Top Champion?!

Liko and the others have come to Area Zero, where they accompany Briar to the place where Entei was spotted. In the meantime, Sango, who had been tailing the group, encounters an odd-looking Purin, and the two of them decide to team up to fight back against the enraged Paradox Pokémon Great Tusk after getting attacked by it?!

Liko and the others finally locate Entei in Area Zero! However, this Entei seems kind of different from normal Entei. Liko, Roy and Dot challenge it to a battle, getting help from Friede as well, but moves that should be effective against a Fire type like Entei aren't having much effect either?! But why...? And will Liko and the others manage to overcome Entei?

The Black Rayquaza once again appears before Liko, Roy and the others, and they all challenge it to a battle together in order to gain its approval! However, despite incorporating the terrain to great effect in their combo attacks, they gradually end up driven against the wall by the overwhelmingly powerful Rayquaza! Liko's wishes... Roy's desire... What's going to happen to them at the end of this fierce battle against the last member of the Six Heroes?!

Rayquaza is guiding Liko and the others towards Rakua. Meanwhile, Amethio had been going undercover at Exceed in order to look into what Spinel is plotting, but got spotted by security guards and captured. And now a certain person appears...? Amethio learns about the connection between his grandfather Gibeon and Lucius from a 100 years back... and makes a resolve!

Rayquaza guides Liko and the others to a mountain towering high into the heavens. They begin asking around for information on Rakua in Kumuri Town, a town located at the foot of the mountain, when they meet a young boy named Yuha who insists they need to get out of the town immediately. As the group soon learns, local legend has it that disaster will strike when the Black Rayquaza appears.

Liko and the others finally arrive in Rakua, which was located at the peak of Mt. Kumli. Here, a virtual paradise spreads out before them, with rich and plentiful nature and many wild Pokémon living in peace and quiet! Deeply moved by this sight, they start searching for 100 year old traces of Lucius. But a certain Pokémon is keeping an eye on them...

In the center of Rakua, Pagogo releases the barrier it set up a 100 years ago... but then the Explorers suddenly appear, having been lying in wait for the barrier to get released so they can obtain the Rakulium...! The decisive battle in Rakua over the Rakulium now begins: Friede VS Spinel, Liko VS Onyx, Roy VS Sango and Dot VS Agate!!

As Gibeon attempts to use Zygarde to dig up the Rakulium, Amethio appears before him and tells him... Meanwhile, Liko and the others come rushing over as well, having seen the overflowing energy. But as they attempt to stop the digging, the Rakulium crystal shatters into pieces and a certain someone appears from within...?!

With the Rakulium crystal before them, Liko and the others square off against Gibeon! Liko, Roy, Dot and now also Amethio engage in a fierce seesaw battle against the mighty Zygarde, who is so overwhelmingly powerful it's difficult to even get near it! As the four fight on, they gradually start finding opportunities to close in on Zygarde, but...

Thanks to Pagogo and the Six Heroes, the Rakulium finally gets successfully purified. However, after a brief moment where everyone believes things are at long last over, Spinel suddenly announces he's going to "take control of" Rakua! He then somehow manages to make the Six Heroes go berserk... Liko and the others attempt to escape as Rakua falls to the rampaging Six Heroes. What lies in wait at the end of the adventure to Rakua?!