Digimon: Digital Monsters - Season 1 - Eps 20: The Earthquake of MetalGreymon
While the rest of the DigiDestined distract Etemon's forces, Tai and Izzy infiltrate the pyramid to save Sora, where Datamon plans on cloning her to use her Crest and Biyomon to enact revenge on Etemon. Tai musters his courage and saves Sora while Datamon activates the Dark Network to absorb data, including Etemon. Etemon, fused with the Dark Network, fights the DigiDestined, but Tai's Crest allows Greymon to Digivolve into MetalGreymon. When Etemon is defeated, a portal swallows him while Tai and Koromon are sent to Tokyo.
About Digimon: Digital Monsters

Title: Digimon: Digital Monsters
First Air Date: 1999-03-07
Last Air Date: 2001-03-25
Status: Ended
Rating: 8.1/10 (from 845 votes)
Language: JA
Seasons: 2
Total Episodes: 104
Network: Fuji TV
Genres: Animation, Action & Adventure, Sci-Fi & Fantasy, Kids
Production Companies: Toei Animation, Toei Company
Synopsis
While at summer camp, seven kids are transported to a strange digital world. In this new world they make friends with creatures that call themselves Digimon who were born to defend their world from various evil forces.
Cast

Reiko Kiuchi
Daisuke Motomiya (voice)

Megumi Urawa
Iori Hida / Armadimon (voice)

Rio Natsuki
Miyako Inoue (voice)

Hiroaki Hirata
Takeru Takaishi (voice)

Romi Park
Ken Ichijouji / Digimon Kaiser (voice)

Junko Noda
V-mon (voice)

Kae Araki
Hikari Yagami (voice)

Koichi Tochika
Hawkmon (voice)

Miwa Matsumoto
Patamon (voice)

Naozumi Takahashi
Wormmon (voice)