To unlock crafting recipes in The Last Stand: Aftermath, you will need to find various resources such as gears and scrap. When you find different materials, you can then unlock crafting recipes by combining them.

If you combine two types of resources into the correct combination, you will unlock the crafting recipe for an item in the game. For example, if you want to unlock bandages, you will first need to get your hands on one rag and one clean water.

Another example would be medkits. To make medkits, you will first need to get one bandage and one alcohol. That said, finding the right item combination is pretty easy, as all you need to do is click on one item and see if any others show up in the list. 

When you click on an item, it will display all potential items you can combine within the crafting menu. So cycle through the list and eventually, you will get the right combination and unlock a crafting recipe.

You can also unlock crafting recipes by unlocking skills with knowledge points. Specific skills under the engineer section will allow players to make various kinds of makeshift firearms if they have the materials. 

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