Spider web

 is obtained by killing spiders in the dungeon. It's only known purpose is as a product of alchemy; once studied, it can be broken down into the Slowing variants of powder and extract.

Alchemy
Spider web can be decomposed to powder and extract with the alchemy mill and either distillation cube, respectively. Having unlocked Master of Alchemy produces one additional reagent at any workstation.

Паутина