Krishna rode a chariot that was heavily potent and once when Arjun was done with the war, Krishna asked him to get off the chariot first and then he got off... As soon as he got off, the chariot exploded... Like a big explosion (Maybe Nuclear types if you ask me) That's when he explained to Arjun why he asked him to get off the chariot first,
Sahadeva knew everything about the future. He knew that a war was going to occur but he kept silent because he was under a curse that if he revealed anything to anybody he would die.
Arjuna's 'pilgrimage' for breaking his marital laws with Draupadi earned him three more wives. They were: Chitrangada (Manipura), Ulupi (Naga) and Subhadra.
Abhimanyu was actually the soul of a daitya named Kalyavana. Krishna after burning Kalyavana to death had captured his soul (tied him in a knot of his upper cloth) and taken him to Dwaraka only to stuff him into a cupboard. Ghatotkacha(who had been sent by Hidimba to take care of Subhadra in Dwarka as Pandavas were in the forest.) saw Krishna and got a scolding from him. He went and reported the matter to Subhadra who went downstairs to check. She opened the cupboard and a light entered her womb which caused her to fall unconscious. This was the main reason why Krishna divulged only half the secret of Chakravyuha to Abhimanyu when he was in the womb.
Ekalavya was actually Krishna's cousin. He was the son of Devashrava (brother of Vasudeva) who got lost in the forest and was found by a Nishada Hiranyadhanu. Ekalavya died protecting his father during Rukmini Swayamvar. He was killed by Krishna. For his great sacrifice of Gurudakshina Krishna blessed Ekalavya that he would be soon reincarnated and take revenge on Drona. This person was Dhristadyumna.
Arjuna was unable to defend the wives of Krishna from common robbers after Krishna's departure to Vaikuntha. His bow became heavy and he forgot all his mantras. The 8 main wives committed suicide. The others were kidnapped by robbers.
Duryodhana had gone to Dwaita forest to humiliate the Pandavas with all the servants from Indraprastha. There the Gandharava Chitrasena and his apasaras were enjoying in the pond. Duryodhana asked Chitrasena to abandon the pool but as he refused, a heated argument broke out between them. Chitrasena attacked Duryodhana. The Pandavas who were nearby asked Chitrasena to let Duryodhana alone. Chitrasena who was a friend of Arjuna spared Duryodhana but not before tying him with vines and setting him on his horse. Duryodhana though humiliated, thanked Arjuna and asked him what he wanted for the turn he had done to him. Arjuna said that he would ask from Duryodhana some other time.
Draupadi was asked 3 times by Duryodhana to come to the court after her husbands lost her in dicing. Draupadi kept denying and asked Duryodhana to question Yudhistira whether he staked himself first or her first. Duryodhana asked Draupadi to question her husband in court directly. Yet Draupadi refused to come and sent the attendant back. Duryodhana lost his temper and ordered Dusshasana to bring her there at any cost.
Yudhistira learnt to play dice form the Sage Vrihadaswa who narrated the story of Nala and Damayanti in their exile.
Bhima had one surviving son named Sarvaga by Balandhara who was not given the throne despite being much elder to Parikshit. He became the ruler of Kashi(his mother's land) instead.
This answer was originally written by me on Quora.