Common Vipers are a group of venomous snakes that includes the adder, which is a six-letter word. Common Vipers are found in Europe, North Africa, and parts of Asia. They are usually small to medium-sized snakes, with some species reaching up to two meters in length. They have a wide variety of color patterns, ranging from solid black to browns, grays, and yellows. Common Vipers are known for their potent venom, which can cause severe pain and swelling. They are also known for their aggressive behavior when threatened.