Question: I've only seen a few episodes so some info would be helpful. After running very fast and for a long period of time, why does the Flash suddenly become very weak?
Question: Who or what is BOB? Where does he come from?
Chosen answer: Killer BOB is a demonic entity that emanates from a realm of pure evil known as the Black Lodge, a place that exists on an alternate plane of reality. BOB feeds on human pain and suffering and can travel on earth by possessing human beings and also as an owl. While possessing humans, he commits horrible acts to elicit pain, fear, and suffering from those who are around him, using that as nourishment. BOB possesses Leland Palmer, later forcing him to abuse, rape, and eventually murder his own daughter, Laura, and later to commit suicide.
Answer: The Flash burns energy the same way a normal human does, just at an extremely high tolerance. His metabolism is incredibly high and he must constantly eat to maintain his energy levels. If he runs at high speed for a long period of time he will burn his stored energy and become very weak.
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