Image via Niantic

Pokémon Go will sometimes have it, so y'all accept to exit of your way to find a certain Pokémon. For example, when information technology'south raining, h2o-type Pokémon will appear far more oft, making it easier to capture them. When it's sunny out, you can expect to see Grass, Fire, and Ground-type Pokémon. At that place are even certain Pokémon forms that appear based on the atmospheric condition, such as Castform. It'due south a conditions Pokémon that has multiple forms, changing depending on the weather in your location. When it's sunny, Castform will be in its sunny form, and if it'due south rainy, Castform'due south rainy form will spawn. Post-obit the Weather Calendar week effect during the Season of Legends, Castform's rainy transformation now has a hazard of being shiny.

For the Weather Week effect, there are multiple means you come across a Castform in its rainy form, and it doesn't accept to be raining out. The atmospheric condition increases the chances of it appearing, simply you should find information technology for the result even when information technology's vivid and sunny. It'll but be spawning in the wild. It will not appear in i-star raids or v-kilometer eggs during the event. Because it's but showing up in the wild, that's the easiest method for yous to observe information technology, but it also means you demand to walk past Pokémon spawn points for whatever chance of catching it. If yous don't want to walk around, your chances significantly get downwards to detect it.

One time the Weather Week event is over, Castform's rainy class will simply appear when it's raining out in your surface area. You lot can always apply incense to effort and lure it to your location while information technology'south raining.

Overall, the best way to take hold of a shiny version of Castform'due south rainy form will be when it'due south raining out, during, and later the Weather condition Week upshot. There's no guarantee you lot'll be able to encounter it in the wild, and then y'all want to try and lure as many as you tin can to your location whenever possible.