The Light Fantastic

Yes. The Light Fantastic begins immediately after The Colour of Magic's cliffhanger ending and is a direct continuation. These two books are the only true duology in the Discworld series.

First published in 1986 by Colin Smythe. It is the second Discworld novel and the second Rincewind book.

Cohen the Barbarian makes his debut here as a very elderly, nearly toothless barbarian hero — the greatest warrior the Disc has ever produced, now in his eighties and dealing with the practical difficulties of a life spent slaughtering monsters. He becomes a recurring character, most prominently in The Last Hero (2001).

The title is taken from John Milton's 1645 poem 'L'Allegro': 'Come and trip it as you go / On the light fantastic toe.' Pratchett adapted it as a metaphor for the unpredictable, improvised nature of Rincewind's survival.

Twoflower returns in Interesting Times (1994), where Rincewind is sent to the Agatean Empire — Twoflower's homeland. The reunion is a significant emotional moment for readers who started with The Colour of Magic.