Bubbly Basin is the first Pokémon Pokopia Expansion Pass area and is introduced as an underwater location.
The area forms Part One of the game’s three-part paid Expansion Pass. It adds an aquatic setting, extra Pokémon, furniture, and a new outfit for Ditto, extending the rebuilding adventure beyond the original land-based environments.
Access to Bubbly Basin is connected to the Dive ability. Players must learn Dive and complete the request “Raise the environment level!” in Bleak Beach before reaching the area’s underwater gate. The game also requires Ditto to know Surf and have the ability to jump.
Bubbly Basin should not be confused with a general Pokopia biome or the name of the entire Expansion Pass. It is specifically the first named expansion area, while later parts are planned to add further content and a new town.