The story starts off on a beach of an unknown island with two Pokeballs washed up ashore, which open to reveal a Chimchar and a Tepig. The two check out their surroundings and watch a Treecko fighting a black shapeshifting creature called a Missingno. Chimchar soon decides to forage in a sitrus berry tree and he runs into the Treecko, who is shown to hate intruders. Tepig meanwhile, watches a red Gyarados attack a Mudkip and an Oshawott. Soon, the five pokemon meet and agree to work together to survive an invasion of Missingnos and their mysterious leader...
Chimchar is the first pokemon seen in the story and soon becomes an unoffical leader of the group. He starts off timid and scared of other pokemon, due to his experiences in the White Forest, but later, he becomes extremley brave as he evolves into Monferno and Infernape.
Like Chimchar, Tepig started off timid and scared due to being picked on by bully pokemon in the White Forest, but he later matures into a brave Emboar by the climax of the story.
Treecko is the first pokemon that Chimchar and Tepig meet, though not directly. He is shown to follow instincts than common sense at the start, mainly because of his trauma over his sensei's death. He was trained to be a powerful force by Most, the White Lucario, but he was killed by Missingnos, as explained in Pokemon Origins. In Pokemon Adventure 2, he has a rivallry with Chimchar.
Mudkip was attacked by a Gyarados and was thrown towards the beach where Tepig was. He later rested in a pool of warm water until he felt better. Mudkip is shown to be friends with Totodile.
Oshawott is the official leader of the group until Chimchar matured. She is smart, knows what to do with mechanics,, and is a decent fighter. She is the one who suggests that they build shelter to avoid the dangers of the jungle. It's later revealed that the structure they built could be used to go to sea, and find a more peaceful place to live. She and other pokemon later upgrade the vessel throughout the course of the story.
Totodile is the last pokemon introduced in the first chapter. He has an austrailian accent and often uses words that austrailians use. He saves the team and their boat from a Missingno ambush as soon as they got into the water. He then joins the group and stays with them throughout the whole adventure. He is seen in Treecko's story of Pokemon Origins.
Missingnos are said to be born without hearts. They wish to destroy the world under their master's wishes. To do this, they must find the seven Missingstones for their master for him to anhilate everyone. They have the ability to shapeshift into other pokemon, and later they can posess special Missingbots for armour. Their leader even captured an innocent pokemon and turned it into a lead general for his army called the Metal Minister.
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