The purans

Once Jaimini, a disciple of sage Vedavyasa expressed his curiosity before Markandeya- 'O Lord! In the great epic Mahabharat, which was created by Vedavyasa, description of Dharma, Arth, Kama and Moksha appears to be intertwined at times and at other times, it appears to be separate from one another. Vedavyasa had described the norms, the stages and the means to perform the duties in all the four stages. This epic contains cryptic knowledge of Vedas. Hence O great sage! I have approached you in order to grasp the full knowledge contained in Mahabharat with your help. Why did Lord take human incarnation even though He is the cause of the origin, perpetuation and destruction of the universe? How did Draupadi become the wife of five Pandavas? How did Balaram expiate for the sin of killing a Brahmin? How did Draupadi's sons give up their lives? Kindly narrate all these things in detail. '