It's possible to reset Mass Outbreaks in Pokémon Legends: Arceus and increase the odds to capture specific Shiny Pokémon. While Outbreaks have been a feature in previous Pokémon games, this is the first time it's been done in such a big open world. Outbreaks are areas in the map where a specific type of Pokémon will spawn rapidly. After speaking with the gatekeeper in Jubilife City, he will mention that one of the five main locations on the map has a Mass Outbreak. Not only is this a great way to catch tons of species of the same Pokémon, but it's also a viable way for capturing tons of Shiny Pokémon.
After completing the Pokédex and unlocking the Shiny Charm item, trainers will have their odds of running into a Shiny Pokémon drastically increased. Combining this Key Item with the additional Shiny Odds buff that is given during Mass Outbreaks makes it much easier to find Shiny Pokémon. The base odds for Shiny Hunting in Pokémon Legends: Arceus is 1/4096. Within a Mass Outbreak, the odds increase from that to 1/158.2, which is a considerable difference players shouldn't ignore. It's worth pointing out that there is no way to control what Pokémon appears in the Mass Outbreaks.
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It's common for trainers to want to hunt for a specific Shiny Pokémon in Pokémon Legends: Arceus. Fortunately, there is a way to reroll which Pokémon are appearing in Mass Outbreaks. All the player has to do is speak with the gatekeeper and go to a location without a Mass Outbreak. Upon arriving, sleep in the nearest tent and change the time of day. Once this is done, return back to Jubilife Village and speak with the gatekeeper. This time, he'll have an entirely new set of Mass
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