DemiDevimon

Digimon Adventure and Digimon Adventure 02 are the first two seasons of the Digimon anime series. Digimon Adventure originally aired from March 7, 1999 – March 26, 2000 whilst Digimon Adventure 02 originally aired from April 2, 2000 – March 25, 2001 as a direct sequel to the preceding series. Both series feature a variety of different characters but mostly centre upon The DigiDestined, a group of children and their partner Digimon who have been chosen to protect the Digital World from various forces of evil. A sequel 6-part movie series titled Digimon Adventure tri. started airing in November 2015.

The DigiDestined (選ばれし子供達^?, Erabarashi Kodomotachi, Chosen Children) are a group of children and their partner Digimon who have been chosen to protect the Digital World from various forces of evil. Each child is given a device known as a "Digivice" which serves many purposes but is mostly used to allow their Digimon partners to Digivolve into stronger forms. Prior to the events of Digimon Adventure, having lost their memories of that event, the eight members of the first DigiDestined group witnessed the battle between a Greymon and Parrotmon at their childhood town of Highton View Terrace prior to moving to Odaiba. They were also witnessed by a group of figures who created the DigiDestined Digimon as part of a project to control the balance between good and evil in the Digital World, each Digimon linked to a Digivice and Crest which are connected to the strongest trait of their respective child. However, when the facility came under attack, Gennai managed to get only seven of the Digi-Eggs to File Island while the eighth Digi-Egg, which eventually became Gatomon, as left behind on the Server continent along with the seven of the Crest stones.

Four years later, whilst attending summer camp on August in 1999, Tai, Sora, Joe, T.K., Matt, Izzy, and Mimi are transported to File Island after receiving their Digivices and then meeting their Digimon partners. While they searched for a way home, the DigiDestined eventually learn of their significance in saving the Digital World as they are led to Server to obtain the Crests to enable their Digimon to assume their ultimate level forms. But when the DigiDestined encounter Myotismon, learning time in the Digital World is faster than the human world, it caused a series of events that briefly allow the seven children to return to Tokyo where they are joined by their eighth member, Tai's sister Kari, and Gatomon once she remembers who she is. The event allow enable Tai and Matt is enable their partners to assume Mega form, making them effective against the Dark Masters and then Apocalymon after they practically destroyed the previous Digital World. Though Apocalymon's defeat allowed the Digital World to return to its original state, causing its time to run in sync with real world time, the DigiDestined end up returning to their world. However a series of events, such as an attack on cyberspace by Diaboromon that had WarGreymon and MetalGarurumon combine into Omnimon, allowed the DigiDestined to reunite with their partners again.

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Wikipedia