This skill is a manufacturing skill which means it is only used when producing certain goods.
The biochemistry skill enables you to create all the potions. Potions are some sort of genetically engineering means, by which most body alterations can be accomplished. The higher the skill, the more production options you will have.
There are potions that can alter the body structure or alter sexual behavior as well as potions that heal illnesses. Some potions can create side effects which must be countered by consuming other potions. Even worse, some potions may cause addictions. There is a more specialized section that deals with this matter in depth.
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