Makeshift Survival Weapon

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Some weapons that you can make out of common materials are: A bow and arrow, An "Atlatl"(AKA:Spearthrower) or the less complex "lacross stick".
How to make a lacross stick is just make a loop or fork and handle out of a branch and then, make a net out of any flexible material and then tie it around the edges of the loop with dug up tree roots as cordage.
But the best of the 3 is the bow and arrow. Because it's most accurate. You can reuse the ammunition. You can hunt from fish, to birds, to small mammals and pros can even hunt bears with a bow(although not advised). And can be made very quickly with the right materials.(See: "Making a survival bow" on youtube)