Quintus Curtius Rufus
Ancient sources present disparate casualty figures for the Battle of Issus. Plutarch and Diodorus Siculus approximate 100,000 Persian deaths, in contrast with the 450 Macedonian deaths reported by Quintus Curtius Rufus. In any case, it is probable that more Persians were killed as they fled than in battle; Ptolemy I, who served with Alexander during the battle, recounts how the Macedonians crossed a ravine on the bodies of their enemies during the pursuit.