Armor of Nessus (5e Equipment)
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Armor (plate), artifact (requires attunement)
Legend says that the Armor of Nessus was created by Asmodeus himself, a gift to a general of his armies, the Pit Fiend Baathrugon following The Reckoning. The armor is said to be indestructible and immune to attacks from even the gods themselves. The armor augmented Baathrugon's powers, and just as any devil who grows in power, he sought to steal his master's throne. The battle raged relentlessly, but ultimately the Archdevil Asmodeus emerged victorious. As Asmodeus turned to destroy the armor, he saw that it was gone. To this day, no one knows what become of the Armor of Nessus. Most believe the armor never existed in the first place. Some believe that Asmodeus destroyed the armor long ago, and that the legend is nothing more than a warning for any who seek the power to dethrone him. But a rare few know the truth, that the Armor of Nessus was never destroyed, but stolen away by the half-devil spawn of Baathrugon.
Blood Contract The Armor of Nessus is incredibly resistant to attunement. Any creature of Good or Neutral alignment that attempts to attune to the Armor of Nessus must make a DC 21 Wisdom saving throw as the armor attempts to destroy the creature of daring to touch it. On a failed save, the creature is affected by the Imprisonment spell using the Hedged Prison form. The condition for releasing the creature is to corrupt another imprisoned creature of good alignment into evil alignment and have them attempt to don a replica set of armor hidden in the demiplane. On a successful save, the creature takes 10d12 Fire damage and 10d12 Psychic damage. Regardless of the result, the armor rejects the attunement attempt.
When a creature of Evil alignment attempts to attune to the Armor of Nessus, they are transported to a pocket dimension that exists outside of time and space. Once there, the creature encounters the essence of the armor. This essence manifests as a Pit Fiend (found in the Monster Manuel on page 77). Work with your DM to determine the nature of this contract, as no two contracts are ever the same. Once a deal has been made, the creature who attuned to it finds themselves back in the plane they previously were with the armor already on them. Anyone perceiving the event would be unaware of the interaction between the creature and the armor. They only become aware of the results once either the creature falls dead, or the armor is instantly donned by the creature.
Daily Struggle Once donned, the Armor of Nessus cannot be removed by any means, even through a Wish spell, and the wearer is compelled through the armor's will to complete the contract it created. While worn, the armor functions as Plate Armour, with the following rules and abilities:
The armor provides Resistance to cold, bludgeoning, piercing, and slashing from non-magical weapons that aren't silvered. The armor also provides immunity to fire and poison, and the poisoned condition. These resistances and immunities cannot be removed except through a spell of 8th level or above, and such effects only last for 1d4 minutes before needed to be re-cast. The armor provides a resistance to magic, granting advantage on saving throws against spells and other magical effects (except those caused by the armor itself). The armor also provides the wearer the ability to take on any of the following physical changes as an action, with a maximum of two per turn: (a) the wearer grows wings; these wings grant the wearer flying speed of 60 feet, (b) the wearer grows claws on each hand; these claws function as light, finesse weapons that deal 1d8 slashing damage, (c) the wearer grows a tail; this tail functions as a reach weapon that deals 1d10 bludgeoning damage, (d) the wearer gains poisonous fangs; these fangs deal 1d6 piercing damage, and cause the target to make a DC 18 Constitution saving throw or become poisoned. While poisoned, the creature takes 2d6 poison damage at the start of each of its turns. The poisoned target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
The Armour of Nessus has a will of its own and is very adamant about its desires. If its wearer acts in a manner opposed to its contract with the armour or against its alignment, a conflict arises. When such a conflict occurs, the armour makes a Charisma check contested by the wielder’s Charisma check. If the armour wins the contest, it makes one or more of the following demands:
If its wielder refuses to comply with the armor’s wishes, it can react by doing one or more of the following:
Charges The Armor of Nessus possesses the following powers, which require charges to use. The Armor of Nessus has 20 charges, and regains 1d6+the wearer's Wisdom modifier charges daily at dawn. Activating any of the powers requires an action, unless otherwise stated. The wearer may choose to attempt to activate the armor's powers by bypassing the charge requirements if it does not have enough charges or attempt to activate a power without expending any charges, but doing so requires a contested Charisma check against the armor. If the wearer fails the contested Charisma check the armor can choose to attempt to take control of its user as detailed at the end of Daily Struggle. The armour gains a +1 bonus to it's Charisma check for every missing or bypassed charge required to use a power. For example, if the wearer has 3 charges, using all 3, and attempts to use Devil Summoning, a 5 charge ability, the armour's check is increased by +2. Each time the wearer attempts to bypass any charges the base DC for any Charisma check made against the armor is raised by +1 for 24 hours or until the next dusk.
Innate Spellcasting The wearer gains a Pit Fiend's talent for magic, using Charisma as its spellcasting ability modifier if the wearer does not already have one. The wearer may expend 3 charges to cast either Detect Magic or Fireball as a 3rd-level spell or spend 5 charges to cast Hold Person as a 5th-level spell, or Wall of Fire as a 4th-level spell. The wearer can only cast each spell 3 times requiring a long rest before the spell can be cast again unless all charges are bypassed when using the spell or if the wearer cast the spell using their own casting abilities.
Fear Aura The wearer can expend 1 charge to radiate and aura of fear. Any creature hostile to the wearer that starts its turn within 20 feet of it must make a DC 21 Wisdom saving throw. On a failed save, the creature is frightened until its next turn. If a creature's saving throw is successful, the creature is immune to the armor's Fear Aura ability for the next 24 hours. This ability lasts for 2d4 rounds, until the wearer falls unconscious, or until the wearer dismisses it as an action. When the duration ends, the wearer can expend an additional charge as a bonus action to extend its duration for another 1d4 rounds. After the spell ends, you must to finish a long rest before you can use this feature again. This does not prevent the wearer from casting any aura spells that do not use the armor's abilities and does not interfere with any overlapping auras since the aura originates from the armor and not the wearer.
Infernal Summoning The wearer can use expend 5 charges to use the power of the Armor of Nessus to summon devils of the Nine Hells. Summon either (a)2d4 Bearded Devils, (b)1d4 Barbed Devils, (c) 1d2 Bone Devils or (d) one Erinyes. Summoned devils appear in an unoccupied space within 60 feet of the summoner, acts as an ally of its summoner, and can't summon other devils. Summoned devils remain for 1 hour, until they drop to 0 hit points and dissapears or its summoner dies, or until its summoner dismisses it as an action. You need to finish a short/long rest before you can use this feature again
The wearer can expend 20 charges to assume the form of a Pit Fiend as though through the Shapechange spell. While in this form, you possess the Pit Fiend's mace as well as any weapons you possess to bring into the form. The Armor of Nessus is always brought into the new form, and functions as a suit of +3 Plate Mail. You need to finish a short/long rest before you can use this feature again