DIGIMON ADVENTURE 02;
Digimon Adventure 02 (2000), also commonly written as Digimon 02/Digimon Zero Two, is a direct sequel to the previous season; taking place three years later. With most of the original characters now in high school, the Digital World was supposedly secure and peaceful. However, a new evil has appeared in the form of the Digimon Emperor (Digimon Kaiser). This new villain is different—he’s a human just like the DigiDestined. The Digimon Emperor has been enslaving all Digimon in sight with Dark Rings and Control Spires and, to make things worse, has somehow made regular Digivolution impossible. Three new children are chosen to save DigiWorld and, along with T.K and Kari, make up the new generation of DigiDestined.
A new generation of DigiDestined, composed of three new children, as well as Kari and T.K. from the original Adventure series, are given a new kind of Digivice known as D3, which allows them to open a gate to be transported to the Digital World through any computer. Another advantage was Armor Digivolution, using a device called a Digi-Egg, (unrelated to the Digi-Egg that defines the earliest life stage of a Digimon) so their Digimon can evolve in the presence of Control Spires. They eventually stop the Digimon Emperor, Ken Ichijouji, thanks to the sacrifice of Wormmon, Ken's partner.
After his defeat, Ken repents for his evil deeds and joins the Digi-Destined as they fight two evil Digimon named Arukenimon and Mummymon. Arukenimon has a unique power to turn the Control Spires into super-strong, artificial Digimon under her control. To fight this new threat, the gang learns of DNA Digivolution, enabling their Digimon to fuse with each other in pairs for more power. Eventually, when the battle was brought to the Real World, the true mastermind, Yukio Oikawa, makes himself known. This man extracts the Dark Spore from inside Ken and implants it into other children who wish for the greatness that the old, evil Ken had. Those spores develop into flowers that harvest the infected children's energy. Eventually, the Digi-Destined confront Oikawa, only to learn he's an extreme loner whose only friend in the world was Hiroki Hida, Cody's father. Hiroki and Oikawa used to play old video games when they were young, eventually becoming obsessed with the Digital World and dreaming of going there one day, but Hiroki dies before they could go together, causing Oikawa great sadness. In the end, an entity springs from this man's body, none other than the real mastermind, Myotismon from the first Adventure season, now reborn as MaloMyotismon.
Unlike Adventure, which was set in the Digital World except for a temporary return to the Real World, Adventure 02 characters shuttle back and forth between the two worlds almost every episode.
This season ended with the help of DigiDestined from all over the world, using the light that existed inside each one of them and their wishes to return the Digital World to a peaceful world again. Oikawa, who is too weak to enter the Digital World, becomes its guardian as he passes away. After peace is restored, the boundary between the Digital and the Real World is broken down, giving every human their very own Digimon companion.