it was loot from the generals from the invasion that the spellbooks came from. came in black, grey, and red, maybe bluish. was when you stole a faction sigil, that corresponding town tram side would be invaded. after all the generals were killed a crimson dragon would spawn. i wanna say around 2008? used to be worth around 5mil per set. (decent amount in 2008) After more dyes came out these decreased in value. And now that minax arties are the same color, i would say its decreased in value to around 2mil per set. the syths originally came from the daemon invasion of magincia, before the destruction, but still spawn. (at least i got one at an EM event recently as loot,)