Nullsteel (3.5e Equipment)
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An inky black metal with a dull luster, nullsteel is in most applications simply a black-colored steel. However, it is almost totally immune to magic and psionics, and can even dispel them in the right circumstances.
Any magic or psionics that would normally target or otherwise affect any item made of nullsteel instead has no effect, but only on the nullsteel. For example, nullsteel armor does not protect it wearer from magic or psionics, and a nullsteel-tipped spear's wooden haft would still be affected by magic or psionics. A line of effect can pass through nullsteel without hindrance, so a fireball cast close to a nullsteel wall would simply pass through. However, line of sight is still blocked by nullsteel.
Nullsteel armor's armor bonus (or a nullsteel shield's shield bonus) to AC is treated as one higher against any magical or psionic attack targeted on the wearer (but this is moot against a touch attack, which doesn't allow armor or shield bonuses to AC). A nullsteel weapon deals 1 extra damage to a target capable of casting spells, manifesting powers, using spell-like abilities, or using psi-like abilities.
If nullsteel is left touching an object or creature (but not simply in an area) under a magical or psionic effect that is susceptible to greater dispel magic for 24 hours, there is a chance it will leech the power from it, mimicking the effect of greater dispel magic. There is a 1% per 24 hours that it has been in contact with the object or creature of this happening, and the chance is rolled every 24 hours. Even a split second that it is not touching the item or creature resets the time.
Nullsteel cannot be made to be magical or psionic through any means.
To make nullsteel, one must start with normal steel. From there, the process is similar to creating a magic item. It takes one day plus another day per pound of metal to create, antimagic field must be cast every day as part of creating the nullsteel, as well as a daily DC 20 spellcraft check. However, the only raw material cost is the cost of the normal steel, and there is no xp cost. If the spellcraft check is failed, the process is failed and must be restarted, but the raw materials are not ruined. Alternatively, the null psionics field power and a daily DC 20 psicraft check can be made in lieu of antimagic field and the spellcraft checks.
Nullsteel has 30 hit points per inch of thickness and hardness 10.