Though the birds in our fanart Cuphead cursor are so small, they are enemies fought in the Aviary Action! Level of Inkwell Isle Two. Nail Birds are depicted as spherical birds that can be yellow or pink and have orange beaks. Nail Birds are about the same size as Cuphead and Mugman's planes, tied with a rubber band to hold long nails as their weapon. If you defeat them will - they explode in a blast of yellow or pink feathers, depending on their color.