Aelfinn and Eelfinn
Soon after his healing, with a message from Elayne to her mother, he left Tar Valon and went with Thom Merrilin to Caemlyn. There he happened to overhear Rahvin, disguised as Lord Gaebril, plotting to kill Elayne, Egwene, and Nynaeve in Tear. He and Thom left for Tear, aided Rand in taking the Stone of Tear, and saved the three women from the Black Ajah. After Rand had secured Tear, Mat talked with Egwene, who reluctantly told him that a freestanding redstone ter'angreal could give him three true answers to any question. She was reluctant to tell him this fact both because it was private information from Moiraine and she worried over what he would decide to do. In Chapter 15 of The Shadow Rising, he deliberately entered it: "Not unless my life depended on it. That's what I promised. Well, burn me if it doesn't!" (The Shadow Rising). He had to decide whether to return to the Two Rivers and save his village, or to continue following Rand's ta'veren pull, which felt like the more natural course. The doorway took him to the land of the Aelfinn, snakelike creatures who would answer his three questions. He asks what he must do next and is told to go to Rhuidean. He then asks why he must go there and is told that if he does not he will die. Thirdly he asks why he would die and is told that if he does not he will be killed by those who wish to prevent his fate. The Aelfinn then attempt to force him to leave their world, but Mat, furious that they lead his questions with their answers, demands to know his fate to which the Aelfinn respond by giving the following prophesy. They prophesied he would: a) die and live once more as a part of what once was, b) marry the Daughter of the Nine Moons, and c) give up half the light of the world to save the world.
In the valley of Rhuidean, while Rand discovered his Aiel heritage, Mat found another redstone doorway, which brought him to the land of the Eelfinn, who resemble foxes. He was expecting to get more answers, so when the Eelfinn offered him wishes instead: he (unknowingly) wished to a) have the holes in his memories filled, b) be free from Aes Sedai channeling, and c) a way to get out of here (The Eelfinn world). His last wish was especially important, because in order to receive any wishes from the Eelfinn at all, a person must use one wish to exit their world. Mat now has the memories of countless historical military leaders and is thus privy to over a thousand years of cultural and military knowledge; he has a foxhead medallion that causes flows of Saidar to simply dissolve when applied to him (the medallion's effect on Saidin is disputed); and Mat was found by Rand hanging by the neck in Rhuidean, suspended from a black-hafted spear - Ashandarei - set across two of Avendesora's branches. Rand managed to revive Mat, though to this day he bears the scar round his neck; he also decided to keep the spear, actually a naginata-like weapon called an ashandarei in the Old Tongue, and it has been his signature weapon ever since. The spear's blade and shaft are engraved with two ravens each, and a caption on the shaft reads: "Thus is our treaty written; thus is agreement made. Thought is the arrow of time; memory never fades. What was asked is given. The price is paid." (The ravens and the words "thought" and "memory" allude to Odin, who, according to myth, is accompanied by two ravens, Hugin ("thought") and Munin ("memory"))
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