Mass Outbreak is a fairly new term for the Pokémon franchise, but it’s really just an evolution (pun intended) of similar ideas we’ve seen in previous Pokémon titles. While the game doesn’t really make a big deal out of these events, it turns out that they’re a very big deal if you’re one of the many Arceus players looking to add as many shiny Pokémon to your collection as possible. Even if you’re not the type of player that has to collect (a shiny version of) them all, here’s a little more information about what Mass Outbreaks are, how to trigger them, and why they’re so valuable.

Pokémon Legends Arceus: What are Mass Outbreaks and How do You Unlock Them?

Simply put, Mass Outbreaks are (mostly) random events that basically tell you when an area has been flooded with a particular Pokémon. They basically increase your odds of finding specific Pokémon in a particular region as long as the event is active. While the outbreaks usually correspond to a certain Pokémon (meaning your odds of finding that creature in the outbreak area greatly increase), there have been some conflicting reports which suggest that the game will occasionally use these events to increase your odds of finding a small pool of Pokémon in that area. However, it’s not clear at this time whether those reported incidents are intentional, exaggerated, or simply the result of an error. There’s no word regarding the official “appearance rate” of these Mass Outbreaks, but it is pretty clear at this point that some players seem to encounter them more often than others. It does seem like beating the main quest increases your odds of one occurring, but it is possible for Mass Outbreaks to occur before then.

Pokémon Legends Arceus: How do You Catch More Shiny Pokémon During Mass Outbreaks?

Interestingly, it turns out that Mass Outbreaks increase the appearance rate of shiny versions of the Pokémon affected by them. While it was initially believed that your increased chances of finding shiny Pokémon during Mass Outbreaks was simply based on the fact there are more Pokémon to find during them (and that may be part of the equation), it seems like Mass Outbreaks also increase the natural spawn rate of shiny Pokémon. To hunt shiny Pokémon during a Mass Outbreak, you really just need to participate in them. The exact odds of finding one are currently being calculated, but one of the more popular estimates I’ve heard floating around is that you’ll probably find a shiny Pokémon during at least one out of every 10 Mass Outbreaks you participate in. A little practical playtime seems to confirm that estimate is at least roughly accurate, but the bigger takeaway here should be that Mass Outbreaks are your best chance to hunt for shiny Pokémon.

Pokémon Legends Arceus: How Do You Trigger a Mass Outbreak?

The bad news is that there is no specific way to trigger a Mass Outbreak. That is to say that there currently doesn’t seem to be a magical series of inputs you can use to start a Mass Outbreak out of nowhere. However, there is a way to increase your odds of eventually encountering one. If a Mass Outbreak isn’t occurring, head to any area on the map and then return to Jubilife Village. This effectively “resets” the map, which also means that it resets the chances for a Mass Outbreak to occur. You’re still depending on the normal odds of a Mass Outbreak naturally occurring (which are low and chaotic), but if you’re on the hunt for shiny Pokémon, this is a great way to maximize your playtime.

Obsidian Fieldlands

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Crimson Mirelands

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Cobalt Coastlands

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Coronet Highlands

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Alabaster Icelands

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