Only special Rockruff can evolve into a Dusk Form Lycanroc, and neither this Rockruff nor Dusk Form Lycanroc can be caught in normal gameplay. But you can get a special gift of this Rockruff as an early purchase bonus with Pokémon Ultra Sun and Pokémon Ultra Moon. Players will be able to receive a special Rockruff that can evolve into Dusk Form Lycanroc via Nintendo Network from Friday, November 17, 2017, until Wednesday, January 10, 2018. Evolve this special Rockruff and have an adventure in Pokémon Ultra Sun and Pokémon Ultra Moon together with your Dusk Form Lycanroc!
You’ll be able to get this Rockruff only for Pokémon Ultra Sun and Pokémon Ultra Moon. Details on the ways to get this special Rockruff will be announced soon, so keep checking back for more information on it and on the upcoming Pokémon Ultra Sun and Pokémon Ultra Moon games, launching November 17 for systems in the Nintendo 3DS family.
Source: Pokemon.com
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