The basic idea of this thread is that among the Indo-Iranian peoples, a fourth branch(if you count Nuristani) emerges around 2000 BC, when it starts to migrate westward, towards Western Ukraine and the Carpathians, bypassing them, eventually invading Greece during the Bronze Age collapse. A syncretic Greco-Indo-Iranian culture is formed, with the language having a heavy Hellenic substrate. Assuming that this happened, what would the culture of this Indo-Iranian Greece look like? How would it influence their neighbors? Would it be able to emerge out of the Greek Dark Ages more quickly than OTL? How would it's society be different?