How to Get Onix in Pokemon Pokopia

Onix is trapped in a cave in Withered Wastelands. Complete the Yawn Up A Storm quest to free it.

Steps

1. Find Onix in cave northwest of Pokemon Center
2. Talk to Professor Tangrowth
3. Build Seaside Tall Grass for Slowpoke (4 Tall Grass + ocean)
4. Guide Slowpoke to Pokemon Center
5. Raise humidity (water, plants, fountains)
6. Set up Rain Dance Site (2 Castform Rain Charms + food)
7. Trigger rain via Slowpoke Yawn, then Kyogre
8. Rock Smash softened clay to free Onix
9. Build Smooth Tall Grass: 4 Dry Tall Grass + Smooth Rock

Onix Specialties

Bulldoze (required for Pokemon Center rebuild) and Crush (makes paint from berries).