Skycracker (5e Equipment)
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Wondrous item, very rare (requires attunement by a creature of good alignment.)
A delicate feather carved out of white marble, roughly ten inches long, with a deep crack in one side. Holds 6 charges, regaining 1d6 at dawn.
As a bonus action, you may hold the feather up and say the command word; this expends 1 charge. Every creature within 100 feet must make a DC 12 Dex save, taking 10d6 radiant damage on a failed save, as countless beams of pure white light fall from the sky. If used in a location not under the sky, the charge is expended to no effect. If reduced to 0 charges, the feather is cracked fully in half, dealing 4d12 radiant damage to everything within 10 feet before losing its magical properties.