Balarama's disappearance is described in the Bhagavata Purana. After taking part in the battle that caused the destruction of the remainder of the Yadu dynasty, he then sat down in a meditative state and produced a great white snake from his mouth, that is, the holy serpent Shesha of whom he is an incarnation. Shesha then carried Balarama into the ocean and out of the physical world.
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