Xerxes, overseeing the battle personally, was shocked that so small a Greek force would dare to give battle to his massive army, so he waited four days before attacking, hoping that the Greeks would retreat in fear. When this did not occur, he sent his troops forward on the fifth day. The next day the result was the same; the Greeks did not budge. Then a Greek named Ephialtes told the Persians of a narrow trail around the pass. Xerxes sent his 10,000 Immortals, his best soldiers, along the trail. The Greeks saw that they would be surrounded. Leonidas ordered all the Greek soldiers except the 300 Spartans and 1,100 allied Greek troops to retreat. Some escaped, but 4000 are said to have fallen. The Spartans and their remaining allies resolved to face the some 190,000 remaining Persian soldiers on two fronts. At dawn on the day all the Spartans knew they would certainly die, they calmly combed their long hair for battle as Spartan warriors always did. When a retreating Greek told a Spartan that Persian arrows would block out the sun, the Spartan replied that he preferred to fight in the shade. The Persians advanced. The Spartans fought literally to the last man. It took all day for the Persians, who outnumbered the Spartans something like 600 to 1, to take the pass. Two of the brothers of Xerxes himself were slain by the valiant Spartans, but in the end, every single Spartan was killed, including Leonidas.