Their purpose is to give Mario and Huey access to the Crimson Tower; however, they are not immediately found at the gate of the tower. Instead, they are located in different areas that correspond to their color, and certain prerequisites must be fulfilled before Mario is given their help. Justice Toad is located in Cherry Lake, Surfing Kinopio is in Bloo Bay Beach, and the Mountain Sage in Daffodil Peak. The Chosen Toads have key-shaped heads which fit into the gate of the Crimson Tower, and they possess telekinetic powers as well as the ability to fly.
After assembling the trio together, Mario needs to hammer them into their keyholes to open the gate. After doing so, the gate opens and they seemingly disappear. However, they are then shown to be alive and are able to communicate through the small holes on the gate. They then encourage Mario to go after the Red Big Paint Star. They are seen again at the Port Prisma festival after Mario defeats Morton Koopa Jr. and reacquires the red Big Paint Star, and once more after the defeat of Black Bowser at the Port Prisma celebration.
Mario can return to the gate of the Crimson Tower at any point, and the Chosen Toads have new dialogue after each Big Paint Star is collected.