The Pokémon GO Winter Holiday Part 2 event runs from December 24 to 29 and brings the debuts of Rolycoly, Carkol and Coalossal while also featuring Dedenne wearing holiday attire and Shiny Eevee wearing a holiday hat. Players can look forward to festive spawns, themed research and a mix of seasonal bonuses throughout the week. With new Pokémon entering the game and limited-time costume picks to chase, this second half of the holiday celebration gives collectors and battlers plenty to work on before it ends. It’s a busy stretch, so trainers may want to stay active to grab everything in time.
Source: Official Pokémon GO blog and Pokemon.com