A fabulously wealthy merchant-prince of the Free City of Pentos, Illyrio is a magister of the city, and is the latest of the patrons of Viserys and Daenerys Targaryen to try and place them back on the Iron Throne, with Viserys promising him offices and wealth and vast domains as his reward for such a service. Massively fat and with a dyed yellow beard, Illyrio moves with curious lightness, like a dancer.
The actor cast in the role is of normal weight, and it seems unlikey that “fat suits” and prosthetics will be extensively used to match the character.
Illyrio Mopatis shelters Daenerys and Viserys, and helps to arrange Daenerys’s marriage to Khal Drogo. He gives Daenerys a rich gift of three petrified dragon eggs on her wedding day, before she and Viserys travel into the Dothraki sea.