In 1985, at age 15, Cassaro became a design assistant and in-between artist for animated cartoons in the Maurício de Sousa studios.
[1] In 1999, Cassaro created with artist Erica Awano the manga book Holy Avenger; it became the longest published non-child-oriented comic in Brazil.
[2] Cassara also worked as author and editor on: In 1995, Cassaro started Dragão Brasil, the first Brazilian monthly magazine specialized in RPG games, and the only one to complete more than 100 editions.
He left that position and worked as an author of RPGs based on licensed video games such as Street Fighter, Final Fight, Darkstalkers and Megaman.
[1] In 2009, Cassaro started writing for Turma da Mônica Jovem, the best selling comic book in South America.