Battle of Gaugamela main Persian infantry was poorly trained and equipped in comparison to Alexander's pezhetairoi and hoplites. The only respectable infantry Darius had were his 2,000 Greek hoplites and his personal bodyguard, the 10,000 Immortals. The Greek mercenaries fought in a phalanx, armed not with a heavy shield but with spears no longer than three metres, while the spears of the Immortals were two metres long. Among the other Persian troops, the most heavily armed were the Armenians, who were armed the Greek way and probably fought as a phalanx. The rest of Darius' contingents were much more lightly armed; the main
Peltast in Persian as takabara and their shields as "taka". The Persians may have been influenced by Greek and Thracian peltasts. Another alternative source of influence would have been the Anatolian hill tribes, such as the Corduene, Mysians or Pisidians. In Greek sources, these troops were either called peltasts or "peltophoroi" (bearers of pelte). In the Hellenistic period, the Antigonid kings of Macedon had an elite corps of native Macedonian 'Peltasts'. However, this force should not be confused with the skirmishing peltasts discussed earlier. The 'Peltasts' were probably, according to F.W. Walbank, about 3,000 in number, although by the Third Macedonian