Lyganium (3.5e Equipment)
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The Ancient Artisans Tool
Lyganium is supposedly the metal of the ancient keepers of the lore of magic when it was in its first developing stages. Only the Artificer base class knows about this metal, and even then its a knowledge History check of a DC of 35. But getting back to the metal, it not only mask the presence of the user so they cannot be traced (tracked you can still be seen) by scent, magic, track, etc. it has an inert attack and damge bonus of +10.
This metal is costs 95,000 per pound, but first you have to know some one who can find it i.e. someone that knew a master weponsmaster artificer about 16,000 years ago
Lyganium has 12 hit points per inch of thickness and 30 hardness