Antimagic Handcuffs

These magical handcuffs are comprised of pure iron and engraved with powerful runes that glow red when it's effects are activated.

When a creature that is bound by these handcuffs attempts to cast a spell that creature must roll a d20, on an 19 or lower the spell is nullified. Additionally, these handcuffs take no damage from spells, cannot be specifically targeted with magic and when a magic item is used on these cuffs, that item does not benefit from its magical abilities.

Whenever a creature shackled by these handcuffs manages to successfully cast a spell, roll a d4. On a 1 the handcuffs shatter, losing all magic properties.