Weapon, Red Iron (5e Equipment)
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Weapon (any melee), uncommon, rare (+1), very rare (+2), or legendary (+3)
Red iron, also known as red steel, is a special type of steel with a red, pinkish, or purplish coloration. Weapons made of this material are completely immune to all forms of rust and corrosion, and heavily resistant to destruction. If a weapon made of red iron is subjected to an effect that would destroy any ordinary object outright, such as a disintegrate spell, roll a d20. On a roll of 9 or lower the weapon is damaged, taking a permanent and cumulative -1 penalty to damage rolls. The weapon is only destroyed if the penalty drops to -5.
Because of red iron's slight anti-magical properties, damage done by red iron weapons are considered magical for the purposes of overcoming resistance or immunity to non-magical damage. In addition, red iron objects are unable to hold magical infusions, bear curses, or be used as the material components in spells.
The uncommon red iron version of a melee weapon costs 100 gp more than the normal version.
Weapons made of red iron that has been refined to a high degree exhibit strong anti-magical properties, represented by a bonus ranging from +1 to +3. When a magic-based creature, such as an aberration, celestial, elemental, fey, fiend, undead, or magical construct is hit with this weapon, it takes additional damage equal to that bonus. When using this weapon to attack a creature shielded by magic, such as with the mage armor spell or magical armor, you gain the bonus to your attack roll.
Creatures and objects hit with this weapon are considered to have been subjected to the effects of the dispel magic spell, with the level of the spell being 2 + the weapon's bonus. In place of the spellcasting ability check required, roll a d20 and add the weapon's bonus.
Additionally, when a creature that is concentrating on a spell is hit with an attack made with a refined red iron weapon, the weapon's bonus is added to the DC of the Constitution check required to maintain concentration on the spell.
The weapon also gains the bonus to the d20 roll it makes to resist damage. When a refined red iron weapon is damaged, the penalty is first deducted from its anti-magic bonus, then its damage rolls.