Pokemon Legends Arceus Mass Outbreaks & Shiny Hunting: Boosting Shiny Odds with the Outbreak Method

"Shiny Hunting" for rare alternate colors of Pokemon has been a popular endgame past-time for series fans for over 20 years at this point, and yet the practice of actually searching for them has never been easier than its current iteration in Pokemon Legends Arceus. The Mass Outbreak mechanic - where a portion of a map might spawn a group of 10+ of the same Pokemon species in a small area - comes tied with highly increased shiny appearance rates compared to normal, allowing for players to easily grind out shinies.

This is big news, and can be paired with the Shiny Charm (rewarded for completing the Pokedex) to significantly boost your shiny odds and add a whole new wrinkle to the concept of catching 'em all. It's all ultimately fairly simple to execute, though there are a few things you're going to have to keep in mind as you begin to use Mass Outbreaks to nab shinies. 

Farming mass outbreaks will mean you catch a whole lot of Pokemon - so don't forget to mass release them to get some useful rewards. For some more powerful Pokemon evolutions, you might be better off evolving them rather than trying to farm them for Pokedex completion. Finally, it's worth noting that it doesn't appear Mass Outbreaks are possible for Pokemon exclusive to space-time distortions, even though outbreaks and distortions can exist on the map concurrently.

How to Know When a Mass Outbreak has Appeared

The sign that a Mass Outbreak has appeared in one of the game's regions

Figuring out a Mass Outbreak has appeared in one of the game's zones is actually fairly simple - when you attempt to leave Jubilife Village, the guard will alert you to the phenomenon before you even have a chance to choose your location. If the gate guard Ress says that he's "hearing reports of one of those mass outbreaks out there," you know you're on.

Alternatively, you'll be able to spot mass outbreaks on your map at any time. These don't just appear on your area map, but also on the broader map, so if you zoom out to see all of Hisui, you'll be able to easily see if a mass outbreak event is ongoing on any of the areas you're currently not at, as there'll be an icon of the Pokemon that's currently breaking out on the map.

This same icon represents the location of the Mass Outbreak on the area map - so drop a pin on that location to head there, where you'll find the outbreak in action. 

How to use Mass Outbreaks to Grind Shiny Pokemon

Finding a Mass Outbreak isn't all that hard, particularly when you've unlocked every area in the game. Finding one for a Pokemon that you like is another story entirely. So, a few things you'll need to know going in:

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  • Mass Outbreaks will only cycle out when you head out, and return from, a zone. You can't simply head to sleep in your house to reset the spawns.
  • Once you've entered a zone, the shiny calculations for the Outbreak are already determined. However, save your game after entering the zone, rather than before.
  • There is a chance that a Mass Outbreak will "stick around" upon returning from a region if it hadn't been depleted. So if the Outbreak didn't hold a Shiny Pokemon, head back to base. If the same Mass Outbreak is there - head back in, save, and repeat. If it's disappeared, then reset your save and return to Jubilife Village and see if the Outbreak is still there. We've noticed that sometimes if you do this and try to 'save scum' outbreaks, an outbreak will remain but the Pokemon will change.
Mass Outbreaks will always show their location on a region's map
A Shiny Wurmple, found within a Mass Outbreak.

Essentially, you save once you've entered a region for 2 reasons - one, if you mess up when catching a Shiny Pokemon when it has spawned, you can simply reset, knowing that the spawn tables will have stayed the same. The other reason is that it makes it quicker and easier to get back into the action after a reset. 

Shiny Odds for Mass Outbreaks

The standard Shiny odds are 1 in 4096, which means the basic shiny appearance rate for Pokemon Legends: Arceus is the same as has been the case for the last several Pokemon generations. However, the rate for Mass Outbreaks is much, much higher. The Mass Outbreak shiny odds are 1 in 158.2.

This is because, for every Pokemon that spawns in a Mass Outbreak, it will roll for Shiny status 25 extra times, which in turn massively boosts your chance of finding a shiny.

In addition, this bonus will also stack with any other buffs to Shiny rates. Extra shiny spawn buffs are obtained by getting a Pokemon's Research Level to 10, finishing all of its research tasks, and obtaining the Shiny Charm. Here's what the rates would look like in each situation:

Shiny Odds in Mass Outbreaks

  • Base: 1 in 158.2
  • Species @ Research Level 10: 1 in 152.9
  • Species @ Completed Research: 1 in 141.7
  • Species @ Research Level 10 + Shiny Charm: 1 in 137.02
  • Species @ Completed Research + Shiny Charm: 1 in 128.49
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A Shiny Wurmple, after a successful Mass Outbreak run.

As you can see, the biggest boost comes from the Mass Outbreak itself, and while there is a notable bump to appearance rates going down the list - it's at the point of diminishing returns. 

With any luck (and some patience), you'll be able to find Shiny Pokemon to add to your collection in no time. Happy hunting!

There's plenty more help with the systems you'll need to exploit to complete the Pokedex on our Pokemon Legends Arceus guides hub, including on other core systems like getting MP by returning lost satchels, Mystery Gift, and type strengths and weaknesses in depth.

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