The Earthquake of Metalgreymon

The Earthquake of MetalGreymon is the twentieth episode of both Digimon Adventure and the Digimon anime series.

Summary
Izzy discovers that Sora and Biyomon are still in the pyramid, in a hidden room, and the group form a plan to rescue her. Meanwhile, Datamon is creating a copy of Sora, which he plans to use to control her digivice and crest and take revenge on Etemon for imprisoning him. While Matt, Mimi and Joe create a distraction, Tai and Izzy head into the pyramid. When Izzy is held up, it's left up to Tai to face his newest fear and pass through the upcoming firewall. He does, and he finds Datamon's hidden room. When Datamon opens up a hole in the floor, Tai manages to get Sora's digivice with her crest, and Biyomon digivolves. Tai and Sora then escape the pyramid, which collapses after being battered. Meanwhile, Etemon has also found Datamon, and the two plunge into Datamon's expanding hole in the floor and into the heart of Etemon's Dark Network. Datamon is consumed, but Etemon takes control of it and rises out of the pyramid to face the kids outside. Agumon, now Greymon, takes on Etemon with Tai by his side, but it isn't enough. Then Greymon digivolves into MetalGreymon, who has no trouble defeating Etemon. However, destroying the heart of the Dark Network creates a dimensional rift, sucking both Tai and MetalGreymon in.