On the fifth day, finding that the Greeks were still in their positions, Xerxes sent the Medes and the men of Cissia (now Khuzistan) with instructions to take the Greeks alive and bring them into his presence. These troops rushed with the greatest courage to the attack. Many were slain, for indeed they were no match for the Greeks in hand-to-hand fighting, but others stepped into their places. The struggle went on during the whole day, with no result except heavy loss to the assailants. On the morrow Xerxes sent his Persian _corps d'élite_, which went by the name of the "Immortals," to the attack, confident that they would be able to force the pass. They met with no better success. Their spears were shorter than those used by the Greeks, and the narrowness of the battlefield did not allow them to take advantage of their superiority in numbers. Herodotus makes special mention of the practised skill which the Spartans displayed. One of their methods was to feign flight, lure the assailants on, and then turn on them with deadly effect. Vast numbers of the Persians were slain; the Greeks also suffered some loss, for the best troops of the East could not have fought wholly in vain, but this loss was very small. Thrice during the day's engagement the Persian king is said to have leapt from the seat from which he watched the combat in terror for his army. Yet another day was spent in a fruitless assault on the Greek position. The Persians hoped to wear out the enemy by incessant attacks. Some must be slain or wounded, and when the total number was so small, even a small loss must tell upon them in the end. As a matter of fact, however, the strength of the Greeks was not sensibly impaired. The space of ground that had to be held was very small, and the Greeks could change their men actually engaged at frequent intervals. The treachery of a native of Malis, a little Dorian state in the heart of the mountains, relieved Xerxes of his perplexity. He offered, for a reward, to show a mountain path by which the Greek position could be turned. The name of this wretch, on whose head a price was set by the General Council of the Greek States, was Ephialtes. It is doubtful whether the secret could have been long kept; but there seems to have been a general agreement that Ephialtes was the guilty man, though other names were mentioned.