Serpent god Naag causes rainfall

To understand why Lord Rato Machindranath was brought to Kathmandu to bring rain to the valley,  it is important to understand that Serpent god, Naag is actually responsible for bringing rainfall.  So what happened to Naag of Kathmandu that caused such severe drought? And what did Lord Rato Machindranath did to the Serpents in order to bring rainfall to Kathmandu Valley?

The legend goes, once during historic times, a Chyang (Newari Rice Beer) drinking competition took place between a local brewer and Lord Gorakhnath, who was on a vacation in Kathmandu.  Lord Gorkathnath drank tons of beer for many days but the supply of the beer never diminished; suspicious of the brewer, Lord Gorakhnath went to investigate and found out that the circular straw rope under the giant beer pot which keept it in upright position was actually not a rope, it was in fact the serpent god.  Because of the influence of the serpent god, the beer supply never diminished.  Then to make the competition fair, Lord Gorakhnath removed the serpent from underneath the pot, also captured all the rest of the serpents in the Kathmandu valley and made an ashan (thrown) and sat on it.  Because the serpents were stuck underneath Lord Gorakhnath and were not free to cause rainfall, a severe drought occured in the Valley.

So then King of Bhaktapur, King Narendra Dev came up with an idea to make Lord Gorakhnath to get out of the Ashan so that the serpents could be freed to make the rain; the idea was to bring Lord Gorakhnath’s Guru to Kathmandu Valley from Asam (now part of India).  When his Guru (who happens to be Lord Rato Machindranath) arrived,  Lord Gorakhnath was obliged to stand up to respect his Guru, there by releasing the serpents, who were then freed and finally made rainfall in Kathmandu Valley ending the severe drought.

Hence, Rato Machindranath is responsible for ending the drought in Kathmandu by freeing the serpents who make rainfall in Kathmandu Valley.