In dire situations, when you need a tool or piece of equipment that you don't have, or when your tools break, it may be necessary to improvise. Improvisation allows you to use and craft items using substitutes for their normal components that you find in your environment, at the cost of reduced item quality and/or durability.
An item that can be crafted requires specific tools and crafting components. If you don't have one or more of the necessary items, you may Search the Area to look for something else to use instead, such as a tangle of tough vines to use in place of twine. Or, if you already have a suitable substitute in your inventory, you may use it to craft the item.
The GM judges how difficult the item will be to craft using improvised parts, and its quality. The normal improvisation penalty is -3 per improvised component used, and -4 per improvised tool. The GM may adjust these penalties depending on how suitable a substitute the item you found is. If your substitute item can serve a nearly identical purpose to the intended item, there may be no penalty at all. Improvised components are consumed during crafting regardless of success, just like normal components.
Add the Improvisation specialty to Crafting checks involving improvised parts.
Improvised melee weapons are anything that can be swung at a creature to inflict damage. When you use an item as a weapon in a way that it wasn't intended to be, the GM decides which melee weapon class it most closely resembles, and uses the stats for that type of weapon and the material the improvised weapon is made out of. The normal improvisation penalty for weapons is -5 quality (-5 damage), and half the durability of a normal weapon of that type and material. The GM may adjust this amount based on how closely the improvised weapon resembles a normal weapon. This penalty may cause small improvised weapons to deal no damage at all, unless in the hands of someone with a high strength to offset their poor quality.
The same quality and durability penalties apply to improvised ranged weapons, armor, and shields.