Yellow Alloys are one of the members of the Fighting Alloy Team that appears in Super Smash Bros. Brawl. They normally appear in Multi-Man Brawl and can be collected as trophies. Their attacks are the same as Mario's, but without Special Attacks. They are one of the hardest alloys to defeat. Yellow alloys can be used as playable characters using hacks.
Yellow Alloys shares their body structure with Mario, but has two horns on the sides of his head. These horns gives the Yellow Alloy resemblance to the small stick-figures that appears in Meteos. Like all Alloys, they have a big white sphere where their face should be, and smaller ones as hands and heels. They also has the team's characteristic wire sphere in the middle of their body.