Complex sentence: Arriving at the Scaean gate he orders several Mykene soldiers to take him to Agamemnon, when they say no and begin to leave he refers to them as idiots, causing one to turn back and stab Khalkeus in the chest.
Split into simpler sentences: Arriving at the Scaean Gate, he orders several Mykene soldiers to take him to Agamemnon. He refers to them as idiots, causing one to turn back and stab Khalkeus in the chest.