The story goes that Karna, the great hero Mahabharata, could not get any food to eat when he went, after his death, to the higher regions, although he could get plenty of silver and gold there. For he had donated plenty of gold and silver but not food!

He prayed to Yama, the god of the death, and through his grace, he returned to the earth during this Mahalayapaksa, he donated again plenty of food and then returned back.

On all the 15 days, offerings are made to the departed manes, including those names or manners of death are not known. Men of the family, generally observe some austerities during these periods, like not shaving the hair or the beard, not cutting the nails etc. Feeding the priest with khir during this period is considered to be highly praiseworthy to the pitrus or manes