Samus

• Unlock an amiibo-exclusive character-themed aircraft, plus a bonus tuning part

Community-reported

• Unlock a costume based on the character (short-hair version)

Community-reported

• Unlock figure in an amiibo-exclusive pose of the character (requires Chibi-Robo amiibo)

Community-reported

• Unlock a special costume

Community-reported

• Give Kirby a Copy ability based on the character's abilities and a health item

Community-reported

• Unlock a character-themed Mii racing suit

Community-reported

• Unlock a Metroid-themed Mii racing suit

Community-reported

• Play a musical jingle

Community-reported

• Change riding music in Sol Valley; once per day, restore health and activate a shield absorbing up to 99 damage.

From NintendoSource

• Unlock an armor paint job based on the character

Community-reported

• Unlock an armor paint job based on the character for use in Blast Ball
• Unlock an armor paint job with additional auxiliary ammo for use in campaign missions

Community-reported

• Unlock a Missile Reserve Tank that restores missiles when they run out. After completing the game, unlock the concept-art gallery.

From NintendoSource

• Unlock a character-based costume

Community-reported

• Unlock a character-based costume

Community-reported

• Unlock a character-based costume with special abilities

Community-reported

• Receive a random title or avatar item, up to five times a day. Each amiibo can be used once a day.

From NintendoSource

• Unlock a character-based Mystery Mushroom costume

Community-reported

• Receive a Spirit of the character
• Battle and train up a computer-controlled Figure Player of the character

Community-reported

• Battle and train up a computer-controlled Figure Player of the character

Community-reported

• Battle and train up a computer-controlled Figure Player of the character

Community-reported

• Receive a sketch of the character from Wario which can be exchanged for in-game coins

Community-reported

• Unlock a character-based Yoshi yarn pattern

Community-reported

• Unlock a character-based Yoshi yarn pattern

Community-reported

• Unlock randomly assigned three-minute NES or SNES game scenes. Subsequent scans change the scene.

From NintendoSource