Western Diamondback Rattlesnake
For a lot of people, you are not in the American Southwest until you encounter a Western Diamondback Rattlesnake. The snake is more tan and smaller than its eastern counterpart, so it can blend in with the scrub and sand. It has significantly big venom glands and unique fangs that allow it to deliver a huge dose of venom when it bites. It is also not aggressive in general, so you better not provoke it!
King Cobra
A lot of venomous snakes are not that big and only rely on venom to stun prey instead of trying to crush the victim underneath its body. Despite this, here is one exception to that rule. The King Cobra can grow up to 13 feet and weigh as much as 30 pounds. The longest one ever documented was 19 feet long. Like the other cobras of Southeast Asia and India, it has a venom deadly enough to cause death in an elephant.