Pausanias Description of Greece 1.4.4

[4] So they tried to save Greece in the way described, but the Gauls, now south of the Gates, cared not at all to capture the other towns, but were very eager to sack Delphi and the treasures of the god. They were opposed by the Delphians themselves and the Phocians of the cities around Parnassus ; a force of Aetolians also joined the defenders, for the Aetolians at this time were pre-eminent for their vigorous activity. When the forces engaged, not only were thunderbolts and rocks broken off from Parnassus hurled against the Gauls, but terrible shapes as armed warriors haunted the foreigners. They say that two of them, Hyperochus and Amadocus, came from the Hyperboreans, and that the third was Pyrrhus son of Achilles. Because of this help in battle the Delphians sacrifice to Pyrrhus as to a hero, although formerly they held even his tomb in dishonor, as being that of an enemy.

[4] So, they tried to save the Greeks [ Hellēnes] in the way described, but the Gauls, now south of the Gates [= Thermopylae], cared not at all to capture the other towns, but were very eager to plunder Delphi and the treasures of the god. They were opposed by the people of Delphi themselves and by the men of Phokis who originated from the cities around Mount Parnassus; a force of Aetolians also joined the defenders, for the Aetolians at this time were preeminent for their vigorous resistance. When the forces engaged, not only were thunderbolts [ keraunoi] and rocks broken off from Parnassus hurled against the Gauls, but terrifying-shapes [ deimata] that looked like armed warriors appeared to the barbarians. They say that two of these apparitions, Hyperokhos and Amadokos, came from the Hyperboreans, and that the third was Pyrrhos son of Achilles. Because of this help in battle the Delphians sacrifice [ enagizein] to Pyrrhos [as to a hero], although formerly they held even his tomb [ mnēma] in dishonor [ atīmiā], as being that of an enemy. 22