Boy as Lantaro was, he showed the skill of an old soldier in dealing with his well-armed foe. While the Spaniards were toiling up a narrow pass of the mountain a strong force of Araucanians fell upon them, and for three hours gave them as sharp a fight as they had yet encountered. Then the Indians withdrew to the strong palisade, behind which Lantaro awaited the foe.
Up the side of the steep mountain rode a party of Spanish horsemen, with the purpose of forcing a passage, but near the summit they were met with such a storm of arrows and other missiles that it became necessary to support them with infantry and artillery. Lantaro, vigilant in the defence, endeavored to surround the Spaniards with a body of his warriors, but the success of this stratagem was prevented by the advance of Villagrau to their support. The battle now grew hot, the artillery in particular sweeping down the ranks of the Indians.
At this critical juncture Lantaro showed that he was a born captain. Calling to him one of his officers, named Leucoton, he said, "You see those thunder-tubes. It is from them our trouble comes. There is your work. Do not dare show your face to me until you have made them your own."
Leucoton at once rushed forward with his company and fell in fury upon the battery, driving back the gunners and capturing their cannon. This successful charge was followed by Lantaro with a fierce attack on the Spanish front, which broke their ranks, throwing them into confusion and putting them to flight. The defeat was ruinous, three thousand of the Spaniards and their allies being slain, while Villagrau was saved with difficulty and at the risk of their lives by three of his men, who picked him up where he lay wounded and carried him off on his horse.
In their flight the Spaniards had to traverse again the defile by which they had ascended. Lantaro had sent men to obstruct it by felled trees, and the few remaining Spaniards had a severe fight before they could escape. The Araucanians pursued them to the Biobio, fatigue preventing their following beyond that stream. The fugitives continued their flight until Concepcion was reached, and here the old men and women were speedily sent north in ships, while the other inhabitants fled from the city in a panic, and started for Santiago by land. All their property was left, and the victors found a rich prize when they entered the city. Lantaro, after destroying the place, returned home, to be greeted with the acclamations of his people.