In which work is Lucius transformed into a donkey?

In "The Golden Ass," also known as "Metamorphoses" by Apuleius, the protagonist Lucius is indeed transformed into a donkey. This transformation is central to the narrative and serves as a pivotal event in the plot. The story follows Lucius, who, fascinated by magic, inadvertently transforms himself into an ass while attempting to use witchcraft. Throughout his time in animal form, Lucius experiences the world from a different perspective, which leads to various adventures and insights.

This transformation embodies themes of change, enlightenment, and the struggles of the human condition. His eventual return to human form serves as a metaphor for personal growth and self-discovery, emphasizing the importance of inner transformation over mere physical change.

The other works mentioned do not focus on Lucius or a similar transformation into a donkey; instead, they explore different characters and themes, which is why they do not answer the question being asked.