If you've jumped on the Pokemon GO app recently you may see a new event.
The Sinnoh Collection Challenge involves collecting a handful of Pokemon.
Two of those happen to shadow Pokemon, Stunky and Snover.
Here's everything you need to know to catch them both!
READ MORE: Pokemon GO Sinnoh Celebration Challenge Guide: How To Catch All Sinnoh Pokemon
Sinnoh Collection Challenge Shadow Pokemon
The only way to get these Pokemon is by beating Team GO Rocket.
Don't worry it's not too tall of a task.
You'll need to find grunts at PokeStops or flying in a hot air balloon and defeat them.
The Team GO Rocket PokéStops have a secret timer of 30 minutes.
When this timer runs out they will be returned back to normal.
How To Catch Shadow Stunky
To catch a Stunky firstly you'll need to find a female Team Rocket Grunt.
They will also have to specialize in Dark-type Pokémon.
They should say “Wherever there is light, there is also a shadow.”
Battle them and you should be able to catch a Shadow Stunky.
How To Catch Shadow Snover
To catch a Snover firstly you'll need to find a male Team Rocket Grunt.
They will also have to specialize in Ice-type Pokémon.
They should say “You’re gonna be frozen in your tracks.”
Battle them and you should be able to catch a Shadow Snover.