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(Japanese: セキエイこうげん Sekiei Plateau) is the ninth and final chapter of the Pokémon Zensho manga.
The chapter starts with Satoshi asleep at home. His mother calls for him to wake up. Since Satoshi ignores this, his Charizard grabs his hair with its tail, waking him up. As he goes downstairs he talks with his mother and then gets ready to leave. Then his Lapras starts to talk to Satoshi about the Elite Four. But when Pikachu hears how Satoshi wants to win against the Elite Four, Pikachu goes over to Satoshi's backpack and grabs his Thunderstone. Satoshi turns around and sees this. Pikachu then uses the Thunderstone on itself and evolves into Raichu. Satoshi is happy that Pikachu has evolved and hugs his newly evolved Raichu.
Then Satoshi gets on his Charizard, says goodbye to his mother, and then flies to the Indigo Plateau. When he arrives, he has his Badges checked and begins his first match with Lorelei. Lorelei sends out Cloyster but when Satoshi sends out Raichu, it is easily beat. After he has beaten Lorelei he now battles against Bruno. Bruno sends out Hitmonlee, but it is easily defeated when Lapras quickly freezes it. His next battle is against Agatha. She sends out Gengar while Satoshi sends out his Alakazam. As her Gengar is easily defeated, it is time to battle against Lance who sends out his Dragonite. Satoshi sends out his Charizard which hits it with a fire attack while the Dragonite uses a laser-type attack. Charizard attacks the Dragonite once again and it is defeated.
Just as Satoshi thinks he is the champion, it is revealed he has yet another opponent, Shigeru. He tells Satoshi that he is the real champion, and he begins the battle. The battle starts with Shigeru sending out Blastoise while Satoshi sends out Charizard. Blastoise uses a Water-type attack, but Charizard hides behind one of the pillars to avoid it, which causes the pillar to crack. Then Charizard slams against Blastoise, which cause it to faint. With the battle won, Satoshi is now declared the new champion, and he thanks all his Pokémon for all the hard work they have done while Shigeru drops his Pokédex. Just then, Professor Oak and Shigeru's sister show up. He begins to compare the both boys' Pokédexes. Suddenly, the cracked pillar starts to crumble, and it falls right towards Shigeru but Satoshi leaps and pushes him out of the way. Afterwards, Shigeru accepts Satoshi as a friend.
Prof. Oak then tells the boys of the cave near Cerulean City. He explains how there are lots of rare Pokémon and a great place to fill their Pokédexes, and it is also where the extremely rare Pokémon Mewtwo can be found. Prof. Oak shows them a picture of it, and both boys decide that they will work together to catch it.