Porygon2 first made its appearance as a Porygon where it was shown being obtained by Blue from the Celadon Game Corner; however, this Pokémon was disobedient and ran away from his new Trainer. After chasing it, Blue accidentally crashed into Red, causing a temporary switch with both Trainers. Porygon was later used against Koga in the Silph Co. Building where it was used along with Pika to defeat the Gym Leader.
In The Primeape Directive, Porygon was used to defeat a group of rampaging Mankey and Primeape after using its ability to move through cyberspace to switch from Blue's Pokédex to Yellow's. It was later used to fight and defeat Agatha's Gengar with help from Koga.
Porygon2 made its first appearance in the FireRed & LeafGreen arc in Red and Blue Make Purple Opponents, where it was used in a Double Battle against Red's Pokémon. It was able to take a Body Slam from Gyara and managed to paralyze him through Tri Attack but was damaged by Snor's Earthquake. It was then seen in Once More into the Unown when it was used to disable Trainer Tower AI "R" so that Blue and Green could rescue their family members. At first, it succeeded but not long after "R" came back online and trapped it with a Virtual Lock.
A † shows that the move was used recently, unless all moves fit this case or there are fewer than five known moves.
Trivia
Despite the games stating that the Porygon line is genderless, the Chuang Yi translation of My, My, My Mimic states that Porygon2 is male. This was corrected in the VIZ Media translation.
Related articles
For more information on this Pokémon's species, see Porygon and Porygon2.