You can't find it from the wild, only trade it while it holding a Dubious Disc.
Porygon-Z is a Normal type pokemon.
porygon z is at the oil field hideout
trophy garden (save in front of the door leading to the owner's office, talk to the owner, if he doesn't say there was a porygon in the trophy garden turn ds off and try again until he says porygon)
it is in OIL field hideout
the upgrade is used to evolve porygon into porygon-z
Porygon-Z is #474 in the national pokedex, and it is a Normal type Pokemon.
To find porygon-z, just go to the oil field hidout and look there(never tried but saw before). P.S. he has very strong ability and life.
you can't. dubious disc is to evolve porygon 2 into porygon z, porygon z is a sinnoh Pokemon and leaf green only goes up to hoeen
In the Pokemon mansion talk to Mr. Backlot and he will say some cute Pokemon gave him a smooch and if it is porygon run in the trophy garden to find one . You will have to trade it when it is holding the Upgrade . That is Porygon2 . Porygon Z you trade a Porygon2 When it is holding the Dubious Disk .
Porygon-Z can breed with Porygon and Porygon2 (its earlier evolutions) when both are of opposite genders. However, Porygon-Z cannot breed with other Pokémon outside its evolutionary line.
Porygon-Z
It evolves Porygon 2 into Porygon-Z when you trade Porygon 2 while it is holding the Dubious Disc.