I bought it on a whim from a bargain bin last year when visiting japan. It was something like 500 yen (3-4 $). Who wouldnt buy a classic intro module like that for such a price?

Thinking about how poison works in PF2E, and the first encounter with the Twigblights, it might be good to have some lesser antidotes the party stumbles upon before that encounter. In 3.5 the Twigblight's poison was a nusiance, in PF2E it could be deadly *side eye to the Fall of Plaguestone module*