Sullivan later taught a course on Dungeons & Dragons at MIT, the first of its kind in the country.
[citation needed] Sullivan joined CEO John Rickets, Mark Acres, Andria Hayday, Gaye Goldsberry O'Keefe, Gali Sanchez, Garry Spiegle, Carl Smith, and Michael Williams to form the game company Pacesetter in January 1984.
[3] In comics, in 1987, Sullivan wrote and drew the humor comic book Wabbit Wampage #1 with Amazing (based on a board game he had earlier developed with Pacesetter).
Sullivan wrote the Dragonlance novelization The Dragon Isles in 2002.
He is the author of Dragonlance: The New Adventures books The Dying Kingdom (July 2004; volume two of the series), and Warrior's Heart (November 2006, the first book in the Goodlund Trilogy).