Mbh 3.187.3a

“O king, towards the end of those thousands of years constituting the four Yugas and when the lives of men become so short, a drought occurs extending for many years. And then, O lord of the earth, men and creatures endued with small strength and vitality, becoming hungry die by thousands. And then, O lord of men, seven blazing Suns, appearing in the firmament, drink up all the waters of the Earth that are in rivers or seas. And, O bull of the Bharata race, then also everything of the nature of wood and grass that is wet to dry, is consumed and reduced to ashes. And then, O Bharata, the fire called Samvartaka impelled by the winds appeareth on the earth that hath already been dried to cinders by the seven Suns. And then that fire, penetrating through the Earth and making its appearance, in the nether regions also, begetteth great terror in the hearts of the gods, the Danavas and the Yakshas. And, O lord of the earth, consuming the nether regions as also everything upon this Earth that fire destroyeth all things in a moment. And that fire called Samvartaka aided by that inauspicious wind, consumeth this world extending for hundreds and thousands of yojanas. And that lord of all things, that fire, blazing forth in effulgence consumeth this universe with gods and Asuras and Gandharvas and Yakshas and Snakes and Rakshasas. And there rise in the sky deep masses of clouds, looking like herds of elephants and decked with wreaths of lightning that are wonderful to behold. And some of those clouds are of the hue of the blue lotus; and some are of the hue of the water-lily; and some resemble in tint the filaments of the lotus and some are purple and some are yellow as turmeric and some of the hue of the crows’ egg. And some are bright as the petals of the lotus and some red as vermillion. And some resemble palatial cities in shape and some herds of elephants. And some are of the form of lizards and some of crocodiles and sharks.