you trade it while holding an up-grade.
Porygon does not evolve by training it levels. You must trade with an Up-Grade attached.
It doesn't.
It will evolve at level 7.
Train it to level 25.
mine evolved at level 18
Porygon doesn't evolve at a level. You need a special item to make it evolve.
Porygon's level dosen't interfere with it's evolution, because Porygon does not evolve through Level Up. You need to trade a Porygon with another Pokemon game. Once the traded Porygon reaches the other game, it will evolve into Porygon-2.
trade while holding up grade and it will evolve into porygon 2
Porygon evolves while being traded while holding an Upgrade.
Porygon does not evolve by training it levels. You must trade with an Up-Grade attached.
you have to trade it to evolve.
For Porygon to evolve you have to trade it whilst it is holding an 'upgrade'. See related links for more info.
Porygon does not evolve at a given level: you have to trade it while it is holding the Up-Grade to evolve into Porygon2. Then trade that while holding the Dubious Disk to get a PorygonZ.
In Pokémon LeafGreen, Magnemite will evolve into Magneton at Level 30.
Level 31.
Level 38.
level 28