( The SH pair in this name is pronounced like a lightened 'sh' in 'she' i.e. like one between s in 'so' and sh in 'she'.)
He was the king of Chedi provinces. He was Krishna's cousin. His mother was Saathvathi, younger sister of Krishna's mother Devaki. His younger brother was Danthavakthra.
When he was born, he had a third eye and a pair of extra hands. The divine voice announced that he would be killed by that person, being taken into whose hands, the boy's extra eye and hand would disappear. Saathvathi would give her baby to every one that visited their house. But the extra eye and hands remained as they were. Once Krishna and Balaraama went to see their aunt. As usual, she gave her son to Balaraama first. No change in the boy's form. When Krishna took him into his hands, the extra eye and extra hands disappeared. Saathvathi understood that her son would fall victim to Krishna. She requested her nephew to spare her son to the extent of a hundred offences done to him. Krishan acceded to her request (Mahaabhaagavatham says this, not Mahaabhaaratham.).
When the Vidarbha princess Rukmini loved Krishna, her brother Rukmi did not like that and decided to give her to Shishupaala. Krishna went to abduct Rukmini and brought her succesfully after defeating all the kings including Shishupaala and rukmi. Eversince , Shishupaala bore a grudge against Krishna. Once he attacked Dvaaraka in Krishna's absence. He also abducted some a womn (Babhru's wife) from Dvaaraka.
During the Raajasooyam of the paandavas, he seriously objected for Krishna being given the supreme honour. He scolded Yudhishthira for that and threw a bitter diatribe against Krishna. Krishna tolerated his cheap talk for some time and in the end, chopped his head off with his discus.
His brother (cousin ) Danthavakthra too was killed by Krishna long before the war.
His son Sahadeva fought on Paandavas side. Later, his another son Sharabha fought with Arjuna during the latter's Ashvemedham expedition after the war. But he stopped the fighting and honoured Arjuna.
"After praying to Naaraayana, Nara, Sarasvathi and Vyaasa, then one should read the Jayam."
DEDICATED TO MY DEAR NIECE VYSHNAVI KRISHNA