Crown of Zion (5e Equipment)
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Wondrous item, rare (Requires attunement.)
This crown was made by the god of madness, Insanis, as a gift to King Zion, the ruler of a long forgotten kingdom. Though the crown drove him mad, his mind was opened to knowledge beyond that of human understanding. This allowed him to bring his kingdom to unimaginable heights.
Insanity Your mind is full of thoughts of Insanis. Your thoughts cannot be read, telepathy does not work on you, and you are immune to frightened and charmed conditions. Any creature that tries to read your mind must make a DC 15 Wisdom saving throw. On failure, the creature must roll for the short-term madness table.