how do i get fire arrow's

[sevastian]

thank you

[JPMcMillen]

You can buy them from the Nomadic Merchant, east of Astray from Caelid Highway North Site of Grace.
The craftable version requires the Armorer's Cookbook #2, 3xThin Animal Bones, and 1 Smoldering Butterfly. With a Flight Pinion you can do a fletched version that has more range.