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Finding the Starmie Doll for Frillish is required as part of Pokémon Pokopia's Bubbly Basin storyline.
Frillish will help you build the Ocean Temple in the Build the Beautiful Building quest once you have fulfilled its request of finding a Starmie Doll.
The process is a little fiddly, so this guide explains how to find Frillish and lure her through the cave, and the Starmie Doll location in Pokémon Pokopia.
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Where to find 'floaty pink one' Frillish in Pokémon Pokopia
As you're putting together a crew to help build the Ocean Temple (you'll need to have started the Build the Beautiful Building quest, which is unlocked by reaching Basin Environment Level 3), Popplio will give you clues on Pokémon who will help out - one of which is described as "the floaty pink one".
You'll be pointed to a cave to the north by heading through the site of the Ocean Temple build, then a little to the left. A screenshot of the cave with Frillish inside, complete with a mini-map of the location, can be seen below:
Talk to Frillish, and you'll be tasked with exploring the cave.
How to find the Starmie Doll for Frillish
Once you have spoken to Frillish and cleared the entrance, you can begin exploring the cave.
Very soon, you'll have to emerge from the water, go across dry land, and back down again. Do so - Frillish will follow - and then let you know she wants to find a Starmie Doll. Though you are recommended to have a Drowsing Machine to help, you don't need one if you know where to look (we'll tell you exactly where below).
From here, the twisting and turning cave is linear until you reach a minecart track on the ground. When you do, follow that instead, until you reach a more open room with some crystals, the track winding around the room, and some star-spotted rocks along the back wall.
Head to the star-spotted rocks, as it's here you'll find the Starmie Doll. Dig away, and behind the first layer you'll find the Doll in question.
(Note: Frillish may struggle to follow you along the way to the Doll. If so, head back and request she follow you by pressing Up on the D-Pad. However, even if she doesn't follow closely, by the time you find the Doll, she should appear next to you anyway.)
Once collected, a relieved Frillish will hand you the Doll to keep, and will then agree to help you build the Ocean Temple with Popplio. Job done!
It might be easiest at this point for Frillish to follow you back to the Ocean Temple building site, so you can ask them to wait there for when the build is ready to start. But if you prefer to come back later, follow the same cave route as you did to reach the Doll, and Frillish will be somewhere along the route.
If you're looking for more help with the Ocean Temple build, then we have a guide explaining how to find Ocean Doors and Seashell Fencing.
Frillish Habitat
Finally, if you're after Frillish's Bubbly Basin habitat, they are as follows:
- Ocean Treasures (Marine Chest x1, Bottled Ship x1, Sparkling Jewelry x1)
- Playing Sailor (Big Treasure Chest x1, Ship's Wheel x1, Wooden Crate x1, Bottled Ship x1)
Frillish can be found all day and in all weather.