After beating the main story, it's possible to get many of Shiny Pokémon in Pokémon Legends: Arceus. Shiny Pokémon have been a staple in the series since the release of Pokémon Gold and Silver, and Legends Arceus is no different. However, these are just the same Pokémon with unique color designs and don't have any game-changing stat boosts or abilities. The real treat of finding these Pokémon is the hunt themselves because of how rare they are the naturally encountered. The base odds of finding a Shiny Pokémon in Pokémon Legends: Arceus is 1/4096. Although, there are a handful of ways for trainers to increase these odds.
The first method is by unlocking the Shiny Charm in Legends: Arceus.It's a Key Item that is rewarded for completing the Pokédex and will drastically increase Shiny odds. Unfortunately, unlocking the Shiny Charm is one of the final challenges in the game, making it difficult for trainers to get it in the early game. Not only that, but reaching a species research level of 10 will increase the Shiny odds for that Pokémon from 1/4096 to 2/4096. On the bright side, it is possible to increase this even further.
Related: Pokémon Legends: Arceus — Ursaring Evolution Guide
To find more Shiny Pokémon in Pokémon Legends: Arceus, trainers will need to participate in Mass Outbreaks. This is a feature in the game that will spawn 4 Pokémon at a time, but defeating the Pokémon in battle will continue to spawn more Pokémon. When leaving to go on an expedition, if there's a Mass Outbreak available, it will show up on the map. If there are no Mass Outbreaks available, trainers should try and reveal more of the map. Having said that, waiting to Hunt for Shiny Pokémon until the end of the game is ideal because every big area
Read more on screenrant.com