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.