Mordenkainen's disjunction

Mordenkainen's disjunction was a powerful abjuration spell that reduced magic items and effects to their basic components, effectively and permanently canceling them. It was also known as mage's disjunction. To Zakharan mages, always reluctant to acknowledge ajami names and accomplishments, the spell was known simply as disjunction, and counted among the spells of the universal province.

Effects
The spell caused all magic effects and items to be broken down (or "disjoined") into their basic components. This had the effect of not only instantly and permanently undoing other spells&mdash;including powerful magics on which normal dispelling or antimagic did not work &mdash;but magic items were stripped of their enchantments and reverted to mundane items. The wearer of a magic item subjected to disjunction might try to assert their own willpower to try to prevent the item from being disjoined. The caster was generally able to exclude their own magical possessions from the effects of the spell.

Mordenkainen's disjunction was so powerful that even magical places, legendary artifacts, and spelljamming helms were not entirely immune to its dissociating magic. There was a chance, albeit small, that an artifact or helm could be stripped of its magic, also permanently maiming the magical capabilities of its wearer. Of course, the destruction of a powerful artifact ran the risk of calling the attention of powerful beings associated with that artifact.

The best way to protect magic items from Mordenkainen's disjunction was to place them inside an area of antimagic, however the spell even had a chance of overcoming the effect of an antimagic field if the caster was sufficiently powerful, in which case any items protected by it would be disjoined as normal.

Mordenkainen's disjunction was one of the few magics powerful enough to cancel the effect of other mighty spells that might otherwise require a wish or miracle to end. For example, it could undo binding spells or powerful guards and wards, and could could also unmake Algarth's embattlement, Belorigar's baldric, greater spell trigger prismatic sphere, and wall of force. It could also be used to counter dispel shunt or antimagic shell, but was not guaranteed to succeed. However, Mordenkainen's disjunction could in turn be countered by dweomerbanish. The Nephthysan spell enduring ward could also protect a magical glyph or symbol against one casting of Mordenkainen's disjunction, but the enduring ward effect would be destroyed in the process.

Components
The spell required only verbal components. This incantation was apparently simple enough that the spell could be cast underwater.

While not a somatic component per se, the caster could use their hands to touch a magic item that they wished to exclude from the effect of the spell.

History
The spell was attributed to Mordenkainen of Oerth, and had found its way to spellbooks in Faerûn and Zakhara, but was considered a rarity as of the mid-to-late 14 century DR. Sammaster included the spell in his Tome of the Dragon, which he distributed to cells of the Cult of the Dragon.

The avatars of both Maanzecorian and the Queen of Air and Darkness were said to wield the spell. Adamantine clockwork horrors were said to be equipped with a wand capable of casting it. As of the, the dracolich Daurgothoth was working on developing a way to wield the power of Mordenkainen's disjunction as a breath weapon.

Despite its primary use for destroying enchanted items, it was possible to imbue an artifact-level item with the powers of Mordenkainen's disjunction. Such an enchantment was greatly sought-after by those who wished to slay mages.