Some of the Greek leaders were anxious to sack Troy; but two, Odysseus and Achilles, were warned by the oracles of their fates if they participated in the war. Odysseus was warned that his journey home would last twenty years, and thus he feigned madness; but his ruse was quickly discovered and he finally agreed to go to war. The Greeks knew that they could never capture Troy without the help of Achilles, who was the greatest warrior in the world. He was practically invulnerable as a fighter, because at birth his mother dipped him in the River Styx, rendering him immortal everywhere except in the heel, where she held him. (Later, Paris discovers this vulnerability and shoots a poisoned arrow into Achilles' heel — thus, we have the term "Achilles' heel," meaning one's vulnerability.) Achilles was warned that if he went to war he would gain great glory, but he would die young. His mother then disguised him in women's clothing, but the sly Odysseus discovered the trick and Achilles finally consented to go.
After a few months, the Greek army gathers at Aulis in Euboea. According to some accounts, they immediately launch an attack on Teuthrania, an ally of Troy, are defeated, and are driven back. Much of the army disperses. During this same period, the prophet Kalchas predicts that ten years will pass before the walls of Troy will fall. The Greeks, or Achaians as they called themselves, do not try a mass attack on Troy again for about eight years. They have not, as many imagine, spent nine years beneath the walls of Troy, as when the Iliad opens. Some scholars consider this first expedition story to be a variant account of the more common story, but many others think that the expedition against Troy was actually made up of two widely separated expeditions.
