Quick Scoop

To get the Toxic Spire Rod in Fisch, you usually need to craft it, not buy it directly. The materials commonly listed are Poisoned Driftwood , Toxic Core , and Murky Thread , plus about 170,000 in-game currency, then craft it at the Ancient Archives.

Materials

  • Poisoned Driftwood : get Driftwood first, then appraise it until it gets the Poisoned mutation; some guides say a Mutation Totem helps.
  • Toxic Core : obtained from a Forgotten Temple puzzle/trial, commonly described as the second puzzle room.
  • Murky Thread : obtained from another Forgotten Temple puzzle/trial, commonly described as the fifth room/puzzle.

Crafting spot

Once you have all three items and the cash cost, go to the Ancient Archives and use the crafting anvil/hall to make the rod.

Fast route

A simple path is:

  1. Farm or appraise Driftwood until you get Poisoned Driftwood.
  1. Clear the Forgotten Temple puzzle for Toxic Core.
  1. Clear the later temple puzzle for Murky Thread.
  1. Head to Ancient Archives and craft the rod for 170,000.

Notes

Some community guides disagree on small details like the exact puzzle number or best farm method, but they agree on the same core recipe and crafting location. If you want the most reliable approach, focus on collecting the three materials first, then craft at Ancient Archives.

TL;DR: get Poisoned Driftwood, Toxic Core, and Murky Thread, then craft the Toxic Spire Rod at Ancient Archives for about 170k.