Wiki:
You won't get Creature Products every time you skin a body. If you see a green spark, the product of the specific Monster will appear in the same container as your Obsidian Knife. If you see a yellow spark, you won't get the product. The chance of getting a dead body skinned successfully may vary from creature to creature.
Nie za kazdym razem lootniesz skorke, roznie, raz sie uda, raz nie, cierpliwosci
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