What are some of the Key challenges faced by Greek mercenaries in Xenophon the Persian Expedition?

In Xenophon's "Anabasis," Greek mercenaries faced several key challenges during their Persian Expedition. They contended with hostile terrain and harsh weather conditions, which complicated their journey through unfamiliar landscapes. Additionally, they experienced supply shortages and the constant threat of ambush from local enemies, including Persian forces. Morale was also a significant issue, as the mercenaries struggled with leadership disputes and the uncertainty of their situation after the death of Cyrus the Younger.