Reference article
Blue Diamond
A rare diamond delivered to the museum.
Finding it
This is story treasure 1. The cave checks for uncollected story entries and creates at most one story treasure room per run. Collect it, then return to town to see its cutscene.
Story reward
A rare diamond delivered to the museum. Returning to town unlocks Shirt ID 46. Later chapters also satisfy earlier chapter reward checks.
Version and distance
The source uses authored position gates, rather than a race win. Exact displayed distances and original Flash gates remain to confirm.