Picture ten thousand soldiers covered in gold. Not metaphorical gold — actual gold bracelets, earrings, and counterweights on their spears. They wore robes of purple and saffron over hidden scale armor. Their bows could kill from 250 meters away. The inner circle — a thousand men called the Apple Bearers — carried spears tipped with golden pomegranates. The rest got silver. These were the Persian Immortals, the most elite fighting force in the ancient world, designed to terrify you before the battle even started.

The place
Persepolis
The Ten Thousand Immortals
The golden warriors who never died — and the night march through mountain forests that won the most famous battle in history
Moral of the Story
“History remembers Thermopylae as a story about three hundred Spartans — but the real story is about ten thousand Persians who marched through mountain forests in the dark and turned a stalemate into a victory. The Immortals did not lose at Thermopylae. They won it. What they lost was the narrative.”
Characters
Source
Herodotus, Histories VII.41, VII.61, VII.83, VII.211, VII.218; Arrian, Anabasis Alexandri 3.11.5; Shahbazi, A. Sh., 'Army i. Pre-Islamic Iran,' Encyclopaedia Iranica; Briant, Pierre, From Cyrus to Alexander (2002); Sekunda, Nicholas, The Persian Army 560-330 BC (Osprey, 1992); Root, Margaret Cool, The King and Kingship in Achaemenid Art (1979)