Xavius's Platemail (5e Equipment)
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Armor (plate), legendary (requires attunment)
Xavius's Platemail gives a +1 bonus to your AC and grants immunity to fire damage.
At the start of your turn the armor gives off a burning aura that deals 2D6 fire damage to every creature within 10 ft. of you. This effect can be activated or deactivated with an action.