The Four Ages of the world narrated in the Avestan Südgar/Südkar commentary of the poetic gathas reminds one of very similar accounts in both Greek and Vedic mythologies.
Südgar is the first of the ancient Avestan commentaries on the poetic gathas or the sacred verses of the seer/prophet Zarathûshtrá. The name Süd-gar/kar means the “creator/producer of advantage.”
Süd-kar commentarial style is to take a verse or word from the gathic original and explain it in reference to mythological narratives found in the Avestan Yašts or ancient hymns. Many passages have parallels in other Middle Iranian texts and the Persian rivāyats or correspondences.
For example we read in Yasna 31.5: “Voice in words to me….of those things that will not be or will be.”
Süd-kar commentary on the aforementioned verse follows by a narration of the 4 ages of the world rooted in ancient Indo European mythological past.
The same account is repeated in the Zand ī Vahman Yasn (ZWY I.3): u-š wan-ēw bun padiš bae deed kee čahár azg padiš büd ék zareen ûd ék aseemín ûd ék pöláwadeen ûd ék áhan abar gûmeex éstád
And he saw the trunk of a tree that had four branches, one golden, and one silver, and one steel and one of mixed iron.
The Südkar apocalyptic account is extremely similar to Mahābhārata. Also a resembling theme could be observed at the saules koks “tree of the sun” among the Balts, as well as the lœraðr tree in Völuspá and Grimnismál in the Norse lore.
Truth is that an depth understanding of the poetic gathas is only possible within the context of ancient Indo European ideas, beliefs, magic of wordplays and worldview.
Hesiod in his Ancient Greek “Works and Days” poem lists 5 ages and calls them Golden Age, Silver Age, Bronze Age, Heroic Age, and Iron Age. Ovid in his Latin(Italic/Roman) “Metamorphoses” poem lists 4 ages excluding Hesiod’s Heroic Age.
Vyasa in his Classical Sanskrit “Mahabharata” poem lists 4 ages and calls them Satya/Krita Yuga, Treta Yuga, Dvapara Yuga, and Kali Yuga. The are of descending quality just like the Greek ages with the Satya Yuga being similar to the Golden Age while the Kali Yuga is an apocalyptic age. The apocalyptic degeneration and then renewal of the Kali Yuga is alluded to further in many of the Puranas and is fully described in the Kalki Purana. The Norse Eddas, representing Indo-European Norse and Germanic religion, also describe a period of hostility and degeneration throughout the world before the renewal called the Fimbul-winter. Kalki, Vishnu’s future and final avatar, fights against the army of the demon Kali(not the goddess).
Interestingly after Kalki/Vishnu defeats Kali he preforms the Vedic Ashwamedha and Rajasuya rituals for the devas/gods. Though different rituals this is somewhat similar to how the Saoshyant and his assistants preform the Avestan Yasna and Haoma rituals for the Ahuras after the defeat of evil and the Frasho-Kereti(making wonderful) in Zoroastrian texts. Another difference is Vishnu’s victory in the Hindu text is cyclical and the decline and the yugas will repeat forever while in the Zoroastrian texts the victory of the Saoshyant and the Ahuras ultimately breaks the cycles of evil and degeneration and progresses. The Zoroastrian concept of eternal progress and lasting renewal influenced Jewish, Christian, and Islamic eschatology.
The degenerate age in Mahayana Buddhism is called Mappo and is roughly the Buddhist equivalent of the Hindu Kali Yuga. Early Buddhism was a school of Shramana philosophy which is indigenous to India but Shramana groups were influenced by Vedic terms and concepts and used many of them which is the source of the general Indo-European influence on Buddhism. Buddhist texts that describe the decline of ages and its cycles in detail include the Cakkavatti-sihanada Sutta from the Theravada school, the Mahasamnipata Sutra from the Mahayana school, and the Kalachakra texts from the Vajrayana school in Tibet. Jainism is another Shramana philosophy/religion that still survives today and it also describes ages of decline and its cycles.