"Pikmin 4: Uncovering the Hidden Onion Varieties"
In Pikmin 4, players can find the Rock Pikmin Onion by reaching the fifth area, Giant's Hearth, and breaking down a Stone Wall using Bomb Rocks. They must defeat the Sovereign Bulblax by throwing Bomb Rocks at its tongue and attacking it with Ultra Spicy-sprayed Pikmin. After defeating the Bulblax, players can dig up the Rock Pikmin Onion and start raising their own population of Rock Pikmin.