The electric eel's natural enemy is humans, and there is no other living creature in nature that can compete with it except for human capture. The electric eel belongs to the bareback electric eel family of eel-shaped South American fish, can produce enough to knock people out of the current, is the strongest discharge capacity of freshwater fish, the output voltage up to 300 to 800 volts, so the electric eel has the water "high voltage line" called.

The electric eel has some cells in its body like a small laminated battery, and when these cells are stimulated by nerve signals, ions suddenly pass through the cell membrane, generating a high voltage between the head and tail of the electric eel.