King Cobra is the only snake that makes its own nest. Why does it make its nest ?

The king cobra is oviparous and constructs a nest of leaves and branches in which it lays a clutch of leathery eggs; the heat from the decomposing leaf pile helps incubate them. The female then remains on or near the nest and aggressively guards it throughout the incubation period until the eggs hatch. Field and zoo accounts report clutches typically in the range of a few dozen eggs and confirm the unique behaviour of nest-building and maternal attendance in this species, which explains why the king cobra makes its own nest—to lay eggs and protect them until hatching [2].

Sources

1. [1] https://nationalzoo.si.edu/animals/king-cobra