Æther Crystal (5e Equipment)
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Wondrous item, rare (red), very rare (green), legendary (blue)
Æther crystals are collections of colorful crystal that are typically around 8 feet tall and 8 feet around. The crystals naturally form underground in clusters where the division between planes is especially weak. They act as generators of wild magic and depending on their color, hold large amounts of latent magic. Æther crystals are prized by wizards, and it is not uncommon to find a collection of these crystals in their lairs.
The crystals come in three different colors, of varying power levels. Red crystals restore a spell slot of 3rd level or below. Green crystals restore a spell slot of 5th level or below. Blue crystals restore a spell slot of 7th level or below.
Magical Battery. This item has one charge. As an action, a creature that has spell slots can touch the crystal and spend a charge to draw a stream of power out of it. The creature restores a spell slot depending on the color of the crystal. The æther crystal regains 1d2-1 charges each day at dawn.
Æther crystals have 25 (5d10) hit points. Any magic damage that does less than the crystal's max hit points is absorbed into the crystal. If the crystal reaches 0 hit points, it explodes, hitting creatures in a 30 ft. radius. All creatures must succeed on a DC 15 Dexterity saving throw or take 4d8 force damage or half as much on a successful save.