Oninaki Wiki

The Alchemist is a shop in Deto at which weapons can be enhanced and customized. It is unlocked at the start of Chapter 1 Part 3, when Kagachi and Mayura are ordered to investigate a series of disappearances.

Services available at the Alchemist include:

Upgrade Weapons
Unwanted weapons can be used as raw materials to upgrade another weapon, improving its attack. Up to eight weapons can be used as materials. The weapons used as materials do not affect the results.
Equip Shadestones
Shadestones can be inserted into a weapon's slots to add various effects depending on the Shadestone used. Once socketed, a Shadestone cannot be removed, but can be replaced by another Shadestone; the old Shadestone is often destroyed in the process, but is sometimes recovered.
Unwanted weapons and shadestones can be transmuted into new items. The list of available transmutations changes after every 100 enemies killed.