Speaking of eels, moray eels have the most startling appearance among eels, with small eyes, gaping jaws and sharp teeth. The teeth are not just sharp, but they’re also hooked, which means that once a moray eel bites you, you have to pry it off, as it won’t release its grip even if it dies. (Yikes!) The green moray eel is particularly fearsome and is often mistaken for a sea serpent.