Report: Old Pokémon Games' Encounter Rates Are Different On Different Days

Illustration for article titled Report: Old Pokémon Games' Encounter Rates Are Different On Different Days

Throughout 2020 the source code for a bunch of Pokémon games has been leaking online. As people are coming through the data, they’re making weird little discoveries, like the fact Gen 4 Pokémon games would seemingly adjust their encounter rates on certain days, like birthdays or the anniversaries of tragic events.


As Polygon report, folks like @shinyhunter_map and @MrCheeze_ claim to have discovered changes in Pokémon Diamond & Pearl’s percentages. On longtime Pokemon developer, writer and composer Junichi Masuda’s birthday, for example, eggs reportedly hatch 10% faster than normal.

While on certain international holidays or important anniversaries encounter rates seemingly go up:

The flipside of this is that reportedly there are a handful of dates, marking the anniversary of events like 9/11 or the atomic bombing of Hiroshima, where the encounter rate goes down.


Patricia’s Polygon piece goes into a number of possible reasons for the percentage changes, like Diamond and Pearl’s Pokétch, an in-game watch that was based on the DS’ real-world clock and calculator. Could be that! Could also just be that like most other games on the planet, the developers working on Pokémon games like to include lil’ secrets wherever they can.

Luke Plunkett is a Senior Editor based in Canberra, Australia. He has written a book on cosplay, designed a game about airplanes, and also runs


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