What is the black oil on the TV show The X-Files?
The black oil, also known as purity or the black cancer, is a sentient, fluid alien virus that resembles a black oil slick and is capable of independent movement. It infects humanoids by entering orifices, like eyes and mouths, and gains control of their victim. The alien colonists use the black oil as their reproductive life force.
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Answer the following query.
What is the black oil on the TV show The X-Files?

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The black oil, also known as purity or the black cancer, is a sentient, fluid alien virus that resembles a black oil slick and is capable of independent movement. It infects humanoids by entering orifices, like eyes and mouths, and gains control of their victim. The alien colonists use the black oil as their reproductive life force.
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