There are a lot of new discoveries awaiting players of Pokémon Legends: Arceus and thanks to its wooden Poké Balls, one of the series' biggest mysteries is finally explained. As in previous Pokémon games, players use these items to capture and hold Pokémon. While Legends: Arceus' catching mechanics have changed, the basic principle behind Poké Balls remains the same.
Since the beginning of the Pokémon series, Poké Balls have been an iconic part of the franchise, appearing on box art, as toys, and in opening movie logos (to name a few). Early trailers for Legends: Arceus showed the Poké Balls would be undergoing some changes - in Arceus, they're made of wood and powered by steam. Since the game takes place in the ancient Hisui region, this made a lot of sense. However, it's what these Poké Balls reveal about Pokémon lore that may come as the biggest surprise.
Professor Laventon is one of the new characters in Pokémon Legends: Arceus. In the opening sections of the game, Laventon explains to players how to use Poké Balls and the various ways catching mechanics are different now. During this time, Laventon says that Pokémon have the ability to shrink on their own. This is a pretty large departure from how fans believed Poké Balls worked in the past.
Legends: Arceus Reveals A Big Secret About Pokémon
In past games, it seemed as if Poké Ball technology caused the Pokémon to shrink once they were captured. However, according to Laventon in Legends: Arceus, this isn't the case. Pokémon already possess the ability to shrink (presumably as a defensive mechanism) and getting hit with a Poké Ball triggers that reaction in them.
This can explain why Pokémon seem to disappear once they run away, and it can also explain the animations in games like Sword and Shield - which show the Pokémon rising up out of the grass and even shrinking back below if a player moves too far away. What largely seems like an animation quirk may have been hinting at bigger Pokémon lore. And now that Laventon has given official confirmation of it in Legends: Arceus, it's canonical that all Pokémon know how to shrink.
This may seem like an odd Pokémon fact to introduce decades after the series first started, but Pokémon are "pocket monsters," after all, so it fits with the naming there. And while this confirms Pokémon can shrink, it also seems to confirm that Poké Balls (at least in Legends: Arceus) don't cause the shrinking. Instead, it's a Pokémon's reaction that's triggered from getting hit. It also doesn't explain the energy conversion of modern Poké Balls or whether or not Pokémon can shrink any time they feel threatened. Still, it's a pretty cool way to shake up lore in Pokémon Legends: Arceus and helps solve one of the series' larger mysteries.