10 King Cobra-shutterstock_36767890_0.jpg

Shutterstock

The longest venomous snake in the world – reaching up to 18 feet in length. When they are confronted, they can literally raise one-third of their body straight off the ground and still move forward to attack, according to National Geographic. The good news is that they tend to be shy and avoid humans when possible, but if they feel cornered they become extremely aggressive.