Ilmater's Retribution (5e Equipment)
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Armor (Plate), Very Rare (requires attunement)
Rumored to have been created by Ilmater himself, this legendary suit of armor magically binds to the wearer when worn, and it cannot be removed at will while in combat. Captured from one of Ilmater's fallen priests, the armor has been tainted.
Cursed. At the beginning of any combat, and on each combat round where the bearer has not yet failed the save, the bearer must make a DC 18 Charisma Saving Throw. On a failed save, the armor consumes them, and the bearer becomes more infernal in appearance.
While cursed, the bearer's movement speed increases by 15 ft. and they may make an additional attack as part of their attack action, however they can no longer track the amount of hit points they have remaining, as the DM does now. If the bearer falls below 0 hitpoints, they do not fall unconscious nor do they need to make death saving throws, as it blocks out all sense or indication of pain. At the start of the bearer's turn, if they have taken damage after their last turn and are not at or below 0 hitpoints, they regain 2d8 hitpoints.
The bearer can continue to make Charisma saving throws at the end of each of their turns, ending the curse effects on a success. After succeeding this save, the bearer is immune to this effect for the remainder of the combat. The bearer can choose to succumb to the curse during combat, at their choosing. If the bearer is at 0 hit points or lower and combat ends, the bearer automatically dies and has one round before having their soul sucked out of their body and forced into the armor. When this happens, the bearer cannot be revived by any means other than wish or true resurrection.
Sentience. Ilmater's Retribution has become a Lawful Evil suit of armor with an Intelligence of 12, Wisdom of 15, and a Charisma of 20. It has no senses outside of what the bearer allows it to see through its own senses. The hellish taint on the armor has already shown itself, and it whispers dark thoughts at the fringes of your mind.
Personality. Ilmater granted this boon to his more devout followers, mandating them to protect those who cannot protect themselves. The taint of Avernus has warped this mandate. While it aims to protect, and urges you to do so, it tends to divulge into much more violent ways of doing so.