* The Colour of Magic (1983): This is his debut, where he is introduced as the naive, but well-meaning tourist from the "Counterweight Continent."
* The Light Fantastic (1986): Twoflower continues his Discworld adventures, accompanied by Rincewind.
Although he isn't directly involved in these books, he's mentioned in *The Wee Free Men* (2003) and *The Amazing Maurice and his Educated Rodents* (2001).