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).[4] He wrote Newstralia issues #1–2, published July–October 1989 by Innovation Publishing. He wrote two issues of Solar for Acclaim Entertainment in 2004.
In July 2000, he wrote the novel The Scorpion, the first book in the Legend of the Five RingsClan Wars novelization series.
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).[5]