Nioh

You can forge an item between missions at the blacksmith. It is located at the starting point (on the map in the form of a large house). Forging requires materials and money. Money is knocked out from enemies, drops from broken objects (boxes, barrels, etc.) and is earned by selling things to the blacksmith.
Materials also drop from enemies. To increase the chance of dropping, you need to collect a Kodama of the desired type and ask for his blessing at the altar for the chance of dropping materials.
You can also obtain materials by disassembling unnecessary things from the blacksmith.
To increase the chance of forging a better item, you need to mine the best materials.
This can be done either by farming (not very convenient), or by crafting from less advanced materials (5 pieces of the previous level = 1 piece of the next), or by disassembling things. The quality of the materials depends on the quality of the item. So if you meet a ghost in all purple, call and kill. If the dropped clothes don’t fit, then you can at least take them apart.