1- RAJA BALI-
The demon king in Hinduism, he is not the vaanar bali [commonly thought due to same names]. He was the king of rakshasas but very devotional. The gods feared that if he will be the demon king then he’ll make demons more powerful and devotional resultedly they’ll overpower the gods. So Bhagwan Vishnu took VAAMAN AVATAR in treta yug. He asked for the land that he can cover in 3 spans of leg. Bali granted it and then Vaaman Bhagwan increased and increased and increased his size. In one span he measured whole earth and in second he measured whole universe and nothing was left for third leg so Bali understood that he is god and said him to keep his leg on his head. Then Vaaman Ji transferred him to Paatal Lok making the dimensions of demons and others different. He is supposed to supply some special knowledge to the Kalki Avatar of Vishnu Ji.
2- BHAGWAN PARSHURAM-
The sixth avatar of Bhagwan Vishnu. He is considered to be powerful and angry sage and Brahman Warrior. He won 21 empires of cruel rulers and established new right kingdoms. In Kalki Puran, He is said to be the guru [teacher] of Kalki Ji. He will give him knowledge of weapons and will prepare him for the final battle against evil. He is also the guru of Bheeshma Pitamah and Karna.
3- HANUMAN JI-
The vaanara roop of Bhagwan Shiva. Ram Ji ordered him to live till the end of this kalpa. He also encountered Bhima [pandava] and also met Tulsidas ji [around 300–400 years ago] also he is the supporter of Kalki and will support him in the final battle against evil. He will have strongest devotion towards Shree Kalki Ji and will be his right hand for esatblishing dharma.
4- VIBHISHANA-
The younger brother of Raavan and the king of Lanka. He was granted to rule Lanka till the end of Kalpa. He may be spreading peace and dharma rule after the end of evil.
5- VEDA VYAS-
The author of Mahabharat and all puranas. He is the son of Satyavati and divine father of Pandu, Dhritarashtra and Vidur. He is expected to guide and inspire Kalki ji.
6- KRIPACHARYA-
He is the second guru of Pandavs and Kauravs. He will teach Kalki Ji warfare and other skills.
7- ASHWATHHAMA-
The son of Dronacharya ,who ki-lled all sons of pandavs wrongly and even fired Brahmastra at Uttara’s womb to end the whole lineage of Pandavs. He was cursed by Krishna ji to live till the end of time and in full pain. Kalki Puran says that He will be helping Kalki Ji in final war and resultedly, he would be freed from his curse by Kalki Ji.
So, these were 7 chiranjeevis but there are more who live forever in time. Like JAAMWANT JI [the bear and the minister of Sugreev and leader of Vaanaras].
No one can say what will happen and how. This is just assumption by me in the light of Kalki Puran.
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