The hilt of a sword.
When used, any spells within 600 ft. that create clouds, fog, sunlight, or otherwise alter the weather, are dispelled.
It may also be used to dismiss or create cloud cover within an area of up to 600 ft. around the user.
It may also be used to cast the Call Lightning spell, as though with a 3rd level spell slot. This spell may be used once, and may be reused at the end of a short rest.
If a Celestial wields this item, a red flicker appears from it when it is used to attack. It now counts as a shortsword that deals 1d10 radiant damage, and confers +2 to attack and damage rolls.
Additionally, casting Call Lightning using this item now extends the radius of the storm cloud to a 100 ft. radius, and is cast as if with a 6th level spell slot.