We know that Kali who is the ruler of Kali yuga incarnated as Duryodhana and Dwapara incarnated as Shakuni.

But what of the other two yugas of Sathya and Treta.

Who rules these yugas? Were they incarnated during Mahabharata ? If yes, then as whom did they incarnate? Apart from Mahabharata did this personification mentioned in some other texts ?