There is more to making the Myrddraal sword than simply quenching it in a living body. Though I am not going to go into details here, it must be a human body. Trollocs, for instance, though much easier to procure, would not work. I wonder what you would get using, say, rabbits? A blade that made your wounds break out in Easter eggs?
The piece in the game could be said to still be human—those pieces that came from humans, anyway; there were other sources too—though they are about the size of moderately large chess-pieces. They retain memories, souls, personalities, but they are part of the game now, permanently slaved to the game and part of it as surely as a cog in a clock is part of the clock. They have no personal volition, though they do have awareness. The only lives they can live are being used in the game. In the Age of Legends, these games were destroyed when found; the choice for the pieces was to remain part of the game or death, since removing them from the board/field meant death in any case. The game is all one, board and playing pieces together. And that is much as I will tell you of it. I don’t want to give away what I might use later on, after all.
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