https://www.polygon.com/2017/10/6/16387146/super-mario-odyssey-amiibo-unlockables-list

Super Mario Odyssey will use all available amiibo to unlock special costumes for Mario, but if your amiibo collection is lacking, don’t worry. Nintendo’s website for the game notes that all “amiibo-exclusive” content will available without using amiibo at all.

It’s a design choice that is becoming rarer and rarer these days, when it seems like every big-budget game launches with a bevy of microtransactions in tow. Even Nintendo has gotten into the season pass game, for example, with The Legend of Zelda: Breath of the Wild. The Switch and Wii U game also locks certain costumes behind amiibo, like Link’s classic green tunic. A recent uproar emerged around Metroid: Samus Returns as well, because its hardest difficulty setting is locked behind amiibo figures.