Gatha Elbaphay frequented the Canto Casino, situated in the coastal city of Canto Bight on the planet Cantonica. This alien was present in 34 ABY. She brought her Sheffi pet, Awgree, along to the casino. When Resistance operatives Finn and Rose Tico were searching for the Master Codebreaker, they walked past Elbaphay, who was standing by a game table with her pet in hand. While at the casino, this patron was seen wearing a black dress and had pink skin and black eyes.
The character of Gatha Elbaphay was brought to life by creature performer Paul Warren in Star Wars: Episode VIII The Last Jedi, released in 2017, which is the second film in the Star Wars sequel trilogy. Chris Clarke used remote controls to operate the animatronic facial movements of Elbaphay, while Daisy Beattie controlled Awgree remotely, communicating with Warren via an earpiece. To aid navigation within the costume, Warren had a monitor connected to a small camera positioned at the front of the suit. Nick Kellington stated that he was initially considered to play the patron alongside Warren during the Canto Casino scene; however, he was ultimately cast as Snook Uccorfay, leaving Warren to perform the patron solo.
The design of Gatha Elbaphay was the work of creature concept designer Luke Fisher, and Michael Kaplan designed the costume she wore. Although the patron isn't named in the film itself, the production team referred to it as creature K010, and on set, she was called the "Dowager alien" or "Duchess." In 2021, Lucasfilm Story Group member Pablo Hidalgo revealed the character's official name to be Gatha Elbaphay, which he had created based on the placeholder name "Ms Elbowface."