"A demon from the US that's taken his training and self-improvement to the next level and 'gone platinum' as a result. His immense physical strength allows him to move swiftly despite his incredibly heavy body."
Platinos is a large muscular figure resembling Gilgaros, except that he has one horn instead of two, a fluffy afro, has eyes with sky blue sclera, wears two pairs of dark metallic gray rings on his wrists and ankles, and wears a cape and loincloth that are sky blue.
As his name implies, Platinos has his entire body (excluding the loincloth, cape, eyes, and the club handle) platinum colored.
Unlike traditional Legendary Yo-kai,Platinos can be befriended through battle. The prerequisite is to clear a quest "Motion Sickness on Helicopter" which is available during the progress of Chapter 8 of the game story.
Platinos can be found on a rooftop in St. Peanutsberg of the Southmond area. However, he won't let the player challenge him unless he/she has the Platinum Pass.
Players can obtain the Platinum Pass by inserting the Dream Coin Platinum or the Dream Coin G1 into the USA Crank-a-Kai. As it is Crank-a-Kai, the chance of getting the Platinos Pass is random, though one can always pull the Platinum Pass if the player uses the Crank-a-kai in Japan. The Dream Coin Platinums and Dream Coin G1 can be obtained by reading the QR codes on the back of certain Dream medals.
After the player got the Platinum Pass, go to the Condor Canyon with the helicopter and talk to Platinos. By giving Platinos a pass, the player can battle the Merican Legendary Yo-kai in a once-a-day battle. There's a chance of befriending Platinos if the player wins.
Alternatively theres a chance of obtaining him and the other Merican Legendaries in a Busters-T Dungeon known as Labyrinth of Muo
Similar to the method in Yo-kai Watch 3 Platinos requires using a Platinum Pass, which is a very rare item obtainable in the Lucky/Oni Crank in certain events.
Using the item transports you to a special area where you can battle Platinos but doing so will consume the Pass item, meaning if the player fails to befriend him they will need to pull another pass from the Crank-a-kai.