Porygon is a Normal-type Pokemon that first appeared in Pokemon Red/Blue. By Pokemon Gold/Silver, it gained an evolution in the form of Porygon2, and by Pokemon Diamond/Pearl, it could evolve further into Porygon-Z. The original method of obtaining Porygon2 was by trading it while it was holding an Upgrade. To get Porygon-Z, trainers would then need to have their Porygon2 hold a Dubious Disc and trade it once more. Pokemon Legends: Arceus simplifies the Porygon evolution line by removing the trading requirement.
Unfortunately, Porygon and its evolutions are not easily accessible in Hisui. Players will need to have made some progress in Pokemon Legends: Arceus' story before they have a possible chance of encountering Porygon. To get Porygon2 and Porygon-Z, they'll need to get two evolution items that can either be bought in-game or dropped from the Porygon-line.
Pokemon Legends: Arceus — How to Get Shiny Charm
After defeating Kleavor, odd dimensions called space-time distortions will start spawning around Hisui. A message will appear at the top of the screen when one starts forming. However, it may take some time for the space-time distortion to fully form. When it does, another notification will appear saying «A space-time distortion appeared!»
Porygon and its evolutions will appear in the space-time distortions in the Crimson Mirelands. Like all other Pokemon in the distortions, Porygon will be aggressive and attack the minute it sees the trainer. Stun it with Mud Balls and Spoiled Apricorns, or send out a Pokemon to battle it.
The Upgrade and the Dubious Disc are still needed to evolve Porygon. However, since Pokemon can't hold items in Pokemon Legends: Arceus, evolutionary items like the Upgrade/Dubious Disc work like
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