Coming in at #5
Black Mamba
Though species like the boomslang or the king cobra are dangerous thanks to their respective poisons, the black mamba is especially deadly due to its speed. Found in the savannas and rocky areas of southern and eastern Africa, the species (which can grow up to 14 feet long) is the fastest of all snakes, slithering at speeds of up to 12.5 miles per hour, which makes escaping one in remote areas that much more difficult. Thankfully, black mambas usually only strike when threatened—but when they do, they’ll bite repeatedly, delivering enough venom (a blend of neuro- and cardiotoxins) in a single bite to kill ten people. And if one doesn’t receive the correlative antivenin within 20 minutes, the bites are almost 100 percent fatal.
Some what off topic.
https://www.businessinsider.com/kobe-bryant-black-mamba-nickname-2015-3
"Kobe Bryant's nickname is "The Black Mamba," a name he gave himself. But for Bryant, the moniker is more than a nickname. It is an alter-ego he created to get through the darkest part of his life.
"In his auto-documentary "Muse," Bryant reveals that he created The Black Mamba as a way to deal with the struggles he was going through off the court in 2003 and 2004."
Interesting.
I like snakes.