Mussato’s Ecerinis (1315), the first tragedy in Italian literature, recalls the dramatic period between 1237 and 1259, when Ezzelino III da Romano ruled over Padua. The intervention of marvelous, fantastic and demonological themes characterizes the entire structure of the work. Thus the article, analyzing six main scenes, investigates the representation of Ezzelino as the son of Satan and the Antichrist; in fact, this particular description serves to his contemporaries as an allegorical example to contrast Cangrande della Scala, the real threat against whom the parenthetical message of the text is addressed.