Depending on its habitat, the king cobra may vary its colour, and it is often darker when in forest than when in open savannah. It has good eyesight and will chase down fleeing prey over long distances. Unusually, king cobras eat only reptiles - mostly other snakes.
The intelligent king cobra is the only snake known to build a nest, which is fiercely guarded by the female. Once hatched, the young are just as deadly as the adults, ready to hunt from only ten days old. The smaller young are vulnerable to mongooses and giant centipedes, but the only threat to the adults tends to come from humans, who kill them for use in medicinal drugs.