Eye of Expansion (5e Equipment)
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Wondrous Item, rare (requires attunement)
A silver eye with a diamond in the center. You can embed the eye in the center of your forehead.
Wearing the eye allows you to attune to six magic items (instead of three).
In addition you can use a bonus action to cast true strike. Once used, the true strike property can't be used again until the next dawn.
Curse. The eye is cursed. Attuning to it curses you until you are targeted by the remove curse spell or similar magic. Removing the eye fails to end the curse on you. Whenever you attune or end an attunement to a magic item (including the eye of expansion), your Intelligence is reduced by 4. If your Intelligence score is reduced to 0, you are stunned until you regain at least one point of Intelligence. Removing the curse restores your Intelligence but removes the extra attunement property.