Pokémon Fan Discovers Secret Changes on Holidays and Tragedies

Beneath their kid-friendly surface, the Pokémon games have always contained plenty of surprises and depth to their mechanics. Now, well over a decade after their release, one dedicated fan has discovered how Pokémon Diamond and Pearl secretly change on days of celebration or tragedy.

As reported by Polygon, Twitter user @shinyhunter_map dug into the source code for the games, when they found that the encounter rate, the probability of running into a wild Pokémon in tall grass, went up by 5% on different holidays and days of historic events, such as Independence Day or the end of World War II in France.

Just found the wildest thing in the sauce of Pokémon Diamond and Pearl, encounter rates getting a 5% or 10% bonus/malus depending on certain dates.

— MAP (@shinyhunter_map) May 29, 2020

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But wait, there’s more! The encounter rate goes up by an additional 10% on two days: Tanabata, the Japanese festival on July 7, and Diamond and Pearl director and composer Junichi Masuda’s birthday. The sly dog.

pic.twitter.com/yKUoHtincN

— MAP (@shinyhunter_map) May 29, 2020

Furthermore, the encounter rate will decrease by 5% on a few select holidays, such as Christmas and throughout the Bon festival, a spiritual celebration in Japan.

pic.twitter.com/68RaZ43qki

— MAP (@shinyhunter_map) May 29, 2020

Finally, the encounter rate will decrease by 10% on New Year’s, the Spring and Autumn Equinoxes and days of tragedy such as 9/11 and the atomic bombings of Hiroshima and Nagasaki.

pic.twitter.com/nPkxLV8keu

— MAP (@shinyhunter_map) May 29, 2020

Polygon couldn’t verify the data itself, but reporters there did reach out to another Pokémon data hacker, Orcastraw, lending more credit to the discovery.

It’s kind of insane to think that something like this went undiscovered for so long after the games’ release, and makes you wonder if there are even more secrets we might discover in the future, if we ever discover them at all. For the time being, we don’t know if similar changes to the encounter rate are present in other Pokémon titles.

For more on Pokémon, check out our editorials on the recent Pokémon Mystery Dungeon quiz and its addictive nature, as well as our review of 2019’s Pokémon Sword and Shield. The first DLC episode for Sword and Shield, The Isle of Armor, launches June 17 on Switch.