Shri Kaalsarp Yantra, Code: AY18 If all the planets are placed on the either ride of the Rahu – Ketu is a then Kalsarp Yoga is formed. It is said that this is formed in the horoscopes of those people who had troubled the creatures living below the surface of earth (Patal Lok). One who has this Yoga in ones horoscope has a long and tough struggle in his life. One of the remedies is to keep the Kalsarp Yantra in the place of worship and pray to it for forgiveness.