In the Iceburg Ruins. You need the event Regigigas.
Iceberg Ruins (requires fateful encounter Regigigas) -Bulbepedia
Hope This Helped :D
How to change your username How to add a user avatar Why was my post hidden? Question etiquette Flags vs Downvotes Anime FAQ Official PokemonDb League
Type a Pokemon name, type, move or ability to see instant results.