Super Mario Maker

Costume Mario
Mario can take on unique forms upon touching a Mystery Mushroom, causing him to transform into Costume Mario. These costumes reference Nintendo and third-party characters, and most of them are easily unlockable by using the amiibo scanning function. There are 153 available costumes in total, 5 of which are from Splatoon.

Inkling Squid
The Inkling Squid is the 62nd costume. He is unlocked by clearing a 100 Mario Challenge on Normal or harder, or by scanning the Inkling Squid amiibo. Pressing makes him pose, revealing his humanoid appearance. The Inkling Squid appears to be dark-skinned with green eyes, and he is wielding a Splat Roller and wearing the Studio Headphones, White Layered LS and Hunter Hi-Tops.

Inkling Boy
The Inkling Boy is the 63rd costume. He is unlocked by clearing a 100 Mario Challenge on Expert or harder, or by scanning the Inkling Boy amiibo. Pressing makes him pose with a Splattershot. His appearance is identical to the Inkling Boy amiibo.

Inkling Girl
The Inkling Girl is the 64th costume. She is unlocked by clearing a 100 Mario Challenge on Expert or harder, or by scanning the Inkling Girl amiibo. Pressing makes her pose with a Splat Charger. Her appearance is identical to the Inkling Girl amiibo, spare the charger in place of the usual Splattershot.

Callie
Callie is the 152nd costume. She is unlocked by clearing the Squid Sisters vs. Bloopers Event Course as Callie, or by scanning her amiibo. Pressing makes her strike her signature pose seen at the end of the Inkopolis News, as well as in various promotional artwork. Her unique squid form is also visible when swimming.

Marie
Marie is the 153rd costume and therefore the last one. She is unlocked by clearing the Squid Sisters vs. Bloopers Event Course, this time as Marie, or by scanning her amiibo. Pressing makes her strike her matching signature pose. Just like Callie, swimming reveals her unique squid form.