Colossus in Suspenders

The Colossus in Suspenders (Dungareed Colossus in the European version) is a treasure that is unlocked when the player scans the Mario amiibo from the Super Mario Bros. series. It looks just like the amiibo, and is worth.

Collecting the treasure
After scanning the amiibo on the area selection screen (in any sector), the treasure will appear in one of the Secret Spots of the area. Then, the player has to retrieve the Colossus in Suspenders in that spot.

Trivia

 * Olimar claims to feel a "special bond" with Mario. This could be a direct reference to Olimar's name being derived from Mario, as well as sharing his red color scheme. And, as Olimar mentions, they both have similarly big noses.