Nearly everything that happens in the Iliad occurs on a beach outside the city of Troy. The beginning of the climax of the story is arguably the death of Patroclus. As shown above, Patroclus dresses in Achilles' armor to trick the soldiers. This results in Hector, the main leader of the Trojans on the battlefield, killing him and stealing the armor.
After Patroclus dies, the Greeks fight to protect and return Patroclus' body to the Greek camp. Hector and the Trojans do not make it easy.
When Achilles is told of Patroclus' death, he begins to weep quite dramatically. Patroclus is described as Achilles' best comrade, and Achilles states, "he whom I valued more than all others, and loved as dearly as my own life" (262). The death of Patroclus is what drives Achilles to rejoin the war.
To avenge Patroclus' death, Achilles enters the battle to fight Hector. After some time of fighting, Hector begins running. Achilles chases Hector around the outskirts of Troy three times until Athena tricks Hector into stopping.
Athena's trick worked in Achilles' favor, so the Greek hero successfully killed Hector. Achilles attaches Hector's ankles to his chariot and drags his corpse across the battlefield.
After Hector's death and Achilles' parading of Hector's corpse, the two sides rest. In this time, the Greeks burn Patroclus' body, Achilles weeps again, and they hold games to celebrate Patroclus' life.