Void-Metal (3.5e Equipment)
From D&D Wiki
Void-metal is an extremely rare metal; this ore type only forms from a coallesced portion of the void that interacts with the prime material plane. It is fairly dense, weighing in 25% heavier than steel for items mostly made of metal. Void-metal gives numerous benefits and the added weight is generally accepted at the great boons for using the material.
The benefits of void-metal are as follows: any creature attacked by a void-metal weapon receives no damage reduction, and this applies to all creatures including gods and is used to weaken angelic warriors when they reach godhood; any creature struck also has their regeneration and fast healing abilities suspended for 10 rounds, and this round count starts again if they are struck in a following round; finally each strike temporarily drains one hitpoint from the maximum hit points a creature has, lasting one hour.
The benefits for armor are considerably less useful as they have a tendency to slowly kill the wearer. When made into a suit of armor void-metal performs the following adjustments: the armor is stronger and able to withstand blows better (+3 to AC); the armor grants DR 10/- and the armor also prevents life draining attacks. However, unlike the weapon versions, the armor also permanently reduces the wearers hit points by one each day. This affects any creature wearing the void-metal, including undead as it isn't a negative energy effect, your life force is drained away into the metal itself.
Void-metal is exceptionally rare but appears once the first angelic warrior enters godhood. In an average coallesced fragment from the void you may be able to make a single weapon. In addition the total number of fragments in 1d4 years will usually be no more than ten but the ores are very common. If a world is being showered with void-metal it is likely to have a connection to the void, which means the world itself is in terrible danger. Look at The Void (3.5e Environment) to see what danger lays ahead for the players.
Price key: 200,000 gp for a single weapon
Hardness for void-metal is set at 50 with 200 hit points per inch.