Spectral Armour (5e Equipment)
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Armor (plate), artifact (requires attunement)
A black set of full plate armour with no arms or boots. In the darkness it almost looks like it doesn't exist at all.
Etherealness While you're wearing this armor, you can speak its command word as an action to gain the effect of the etherealness spell and become immune to non-magical damage, which lasts until you remove the armor or use an action to speak the command word again. This property of the armor can't be used again until the next dawn.
Destroying the Spectral Armour. When you attempt to destroy this Artifact it phases to the ethereal realm and reappears. It seems it is untouchable, even by magic.