17 Best images about Mermaid Merman Costume on Pinterest Halloween Majestic Mermaid Costumes : mermaid costumes Majestic Mermaid 8 4x6 Hillary's Handmade Deluxe mermaid costume 4 piece complete set Artofit. They're sure to hear your siren song in this Majestic Mermaid costume featuring a purple corset with sequin details, a lace up back, a long blue sequin mermaid tail with a layered organza skirt and a shell tiara.