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
Ancient Greek warfare Datis and Artaphernes to attack Attica, to punish Athens for her intransigence. After burning Eretria, the Persians landed at Marathon. An Athenian army of c. 10,000 hoplites marched to meet the Persian army of about 25,000 troops. The Athenians were at a significant disadvantage both strategically and tactically. Raising such a large army had denuded Athens of defenders, and thus any attack in the Athenian rear would cut off the Army from the City. Tactically, the hoplites were very vulnerable to attacks by cavalry, and the Athenians had no cavalry to defend the flanks. After several days of stalemate at