Umbral Incense

A flask you open, and it perfumes ten outings in a row with +5% rare chance. That sounds modest, and per outing it is; the point is that rares are the game's bottleneck — recipes, tools, the Atlas — and this is the only rare boost that lasts a whole window instead of a single shot. Which is exactly why the game keeps an eye on it: it's one of the three rare boosters the Almanac calendar is forbidden to give away.