10. Black mamba

Black mambas are some of the scariest snakes on the planet. Named for the dark, inky color inside of their mouths, black mambas are actually brownish in color. They average around 8 feet (2.5 meters) in length.Fast and deadly, these blue-tinged snakes are thought to be responsible for up to 20,000 deaths a year, though precise numbers are hard to come by.