Treta yuga has witnessed 3 incarnations of Lord Vishnu. Vamana Avatar (5th), Parashurama Avatar (6th) and Rama Avatar(7th).
- Vamana Avatar
The Vamana Avatar is the first Avatar in which Lord Vishnu incarnated as a human.
The demon king, Bali, was fair and righteous, yet for all his virtues, Bali was extremely proud and driven by ambition. After conquering the Paatala Loka and all the Earth, Bali managed to win the Heavens from the God Indra. Unable to reclaim his seat, Indra requested Vishnu for aid, and so Vishnu took the form of a dwarf man, a priest named Vamana.
During the Yagnya, Bali was giving gifts to the pious. Vishnu, as Vamana carrying a wooden umbrella, requested only as much land as he could cover in three steps. Bali offered Vamana an island but Vamana stuck to his request, which Bali granted against the wishes of his advisor. Immediately, Vamana grew to cosmic proportions filling the sky. With one step, he engulfed all the Earth and the Paatala Loka. With a second step, he consumed the heavens.Now, with everything under his two feet, Vamana had nowhere to place his third step. He challenged Bali to go back on his word or offer somewhere else for him to step. Bali offered his head as the third step. Vamana sends Bali to the Paatala Loka but, in recognizing Bali’s good qualities, shows mercy by granting him sovereignty over it in appreciation of Bali’s sacrifice.
- Parashurama Avatar
In Parashurama Avatar, Lord Vishnu incarnates himself as a brahmana warrior. He incarnated in this world to avenge all kshatriyas who had become arrogant and were suppressing the brahmans in the world. He was born to the Sage Jamadagni and Renuka, and belonged to the Brighu clan. Parashurama was always carrying an axe presented to him by Lord Shiva of whom he was an ardent devotee. Kartavirya a powerful king, once went to Jamadagni's home when he was out, and after a meal, asked the Kamadhenu cow, which was supposed to give endless quantity of milk. When Jamadagni refused to give, he killed Jamadgni.
Parashurama was enraged at this and went and avenged the death of his father by killing all kshatriyas in 21 battles.
- According to Bhavishya Purana, King Bharata, Nala, and Nahusha lived during Treta Yuga. So the major incidents like Dushyanta-Shakuntala, Nala-Damayanti and Nahusha becoming Indra might have happened during Treta Yuga.
