How To Obtain A Treasure Map Unlike some other rare items in Fisch, you can't get a Treasure Map just by purchasing it somewhere.

Update: Treasure maps are now easier to find than ever in Fisch, with one now likely to appear within every couple hundred of catches. We've also added some new information on how to see your own ...

To acquire Heaven's Rod in Fisch's Northern Expedition, you must complete a puzzle and find all the hidden buttons scattered across the islands.