Angor spent almost the entire night searching for a clue, and he finally saw a book which described how a group of healers saved lives in ancient times. Probably to idolize them, every doctor carried a shining rod decorated by a serpent-like object.
There were even story strips that told a story in history. A man with the serpent rod saw a "shining cloud" as an omen, which led him to a city plagued by a serious illness. He went there and managed to save the suffering patients.
If it were not superstition, Angor would assume that the "shining cloud" was some kind of large-scale healing spell.
There was the "serpent on rod" picture at the end of the book again.
It wasn't a doctor's tool this time, but a giant statue placed in the middle of a plaza, where a number of doctors in healer robes paid their respect to it.
The picture that showed a solemn scene had a line written beneath it.
[Doctor's Oath]