Ring of Mirror Image (5e Equipment)
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A clear crystal misshapen orb rests on an obsidian band that reflects several images back at its wearer. This ring holds 3 charges, and are restored after a long rest.
While wearing this ring, you can use one charge cast a minor version of Mirror Image on yourself as a bonus action. Instead of 3 copies of yourself, only 2 appear. Each time a creature attacks you, roll a d20 to see if it hits you or one of your copies instead. Rolling 6 or higher if you have both, or 8 or higher if only one is left will result in the copy getting hit instead of you. A copy's armor class is 10 + your Dexterity modifier and any successful hit will destroy it. You may dismiss the copies as an action. The spell ends early if both copies are destroyed.
An opponent is immune to the effects of this spell if it can't see, relies on other senses to perceive the world, or if it can see through illusions.