Jörmungandr
The King Cobra (Ophiophagus hannah) is the largest of the venomous land snakes, growing up to 18.5 ft in length. However, as they are generally slender, King Cobras usually do not exceed 44 lb. Its venom is a neurotoxin, capable of killing a human. The mortality rate can be as high as 75%, but most bites involve nonfatal amounts. Although called a cobra, it does not belong to the same genus as the so-called "true" cobras. The King Cobra is peculiar in that it feeds almost exclusively on other snakes, which is reflected in both its common name and its genus name (Ophiophagus is Greek for "snake-eater"), and is even known to attack larger snakes, including pythons. In spite of the King Cobra's fearsome reputation, however, it is generally a shy and reclusive animal, avoiding confrontation with people as much as possible. There are many smaller venomous snakes within this species' range that are responsible for a far greater number of fatal snake bites.
The King Cobra can lift a third of its body off the ground. In effect, an 18 foot King Cobra could actually look down onto the average human being. Like other snakes bearing the cobra name, the King can also flatten its neck, giving it the distinctive hood.
According to the Prose Edda, Odin took Loki's three children, Fenrisúlfr, Hel and Jörmungandr. He tossed Jörmungandr into the great ocean that encircles Midgard. The serpent grew so big that he was able to surround the Earth and grasp his own tail, and as a result he earned the alternate name of the Midgard Serpent or World Serpent. Jörmungandr's arch enemy is the god Thor.