Nagarjuna

Nagarjuna is the son of Arjun and Uluchi….due to a curse by a muni and his wife to Uluchi(She had thrown a stone on pigeon’s nest and an egg fell off and broke which angered the muni and wife who were at that time cursed as pigeons though Uluchi got rid of them of their curse from being pigeons to humans but at the same time the stone she threw made the egg fall from nest and broke and due to this muni’s wife cursed her that she too suffer similarly without her son and husband for a long time) she was cursed that both her husbaand and son will not remember their relationship however later muni’s wife broke the curse saying that Arjuna will remember everything once thrishul and chakra clash against each other. Also, there is a fight between Arjuna and Nagarjuna(who was looked after from birth by Goddess Parvathi) and the unending fight culminates in Parvathi sending Thrishul against Arjuna and Arjuna calling for Krishna’s help and Subhadra too asking Krishna to save her husband and Krishna sends his weapon Chakra to clash against the Thrishul and that’s when Arjuna remembers his stay in Nagalok and his marriage to Ulupi.

https://en.wikipedia.org/wiki/Ulupi

Since Pandu maharaj would have gone neither to Swarg or narak due to his deeds against a muni and his wife and he would reach moksh only after rakhtha tharpana(blood sacrifice) of a boy with shrungi on his head and this happens to be Nagarjuna. He sacrifices himself to give moksha to his pithamaha(grand father) and Nagarjuna’s last words to Krishna that he never got a chance to serve the lord to which Krishna says that in his next incarnation he would be born as Buddha and Nagarjuna will be his greatest disciple and he would get a chance to serve him to his fullest then.

https://www.google.com/search?q=nagarjuna+buddha

Source
http://longestepic.blogspot.com/search/label/Sarala

Serial
https://www.google.com/search?q=Nagarjun+Ek+Yoddha