2

The Production Release Order is as follows (these are the Japanese Air Dates): Digimon Adventure - March 7, 1999 to March 26, 2000 [Series] Digimon Adventure Movie (Part one of Digimon: The Movie) - March 6, 19991 [Movie] Digimon Adventure: Our War Game (Part two of Digimon: The Movie) - March 4, 20001 [Movie] Digimon Adventure 02 - April 2, 2000, and ...


2

In terms of the Digimon regressing: As for the portal appearing:


Only top voted, non community-wiki answers of a minimum length are eligible