"Iron Mace" Alvida is the captain of the Alvida Pirates and the first antagonist encountered by Luffy in the anime present timeline in the manga, Higuma was the first villain). Due to her actions, she can be regarded as the tertiary antagonist of the Loguetown Arc. She is one of the two captains of the Buggy and Alvida Alliance. She was the acting captain of both crews during Buggy's time in Impel Down and during the Summit War Saga. After reuniting with Buggy, his army of Impel Down Convicts, and Galdino (and with the addition of Buggy becoming a Shichibukai), her alliance with him has evolved into the Underworld Organization known as Buggy's Delivery
Originally, Alvida was a tall and very obese woman with long wavy black hair, and freckles on her cheeks.
She wore a white cowgirl hat with a large red plume, a red neckerchief, a pink plaid shirt, and a blue captain's coat over it with the arms in the sleeves unlike many other pirates. She wore rings on her fingers and her long sharp fingernails had red polish. She had a purple sash with a flintlock pistol tucked in it and some jewels. She also wore graying pants and red shoes with gold buckles.
By eating a Devil Fruit, Alvida has transformed by shedding the excess weight from her body. The Sube Sube no Mi makes Alvida very slippery and, aside from the cowboy hat she wears, Alvida looks totally different from her original form, being slim, well-endowed, with dark-green eyes (before is brown), while maintaining her original hair.
She still has her cowboy hat, but she now dresses in a pearl necklace, a bikini top, and tight Capri-length pants. She sometimes has a purple coat draped over her shoulders. She wore a pair of sandals (shoes later in the Post-War Saga in the anime), and now tends to wear shoes that can slip off easily so she can use her Sube Sube Spur technique with the slippery soles of her feet. She still wears lipstick, polish on her now shorter fingernails, and her toenails are shown painted as well (something that before was not visible before due to her shoes). During her appearance in Loguetown, she also had a cape-like, pink cloak with red hearts on it.
Most people that see her actually fall in love with her (as seen in Loguetown, even women), similar to Boa Hancock. Delusional (or, most likely, in denial) on her former appearance, Alvida comments that her change after eating the Devil Fruit was simply that it "made her freckles disappear".
After the timeskip, she replaced her cowboy hat with a red-and-white top hat.