
Spectral Rust Monster
Description
The Spectral Rust Monster is a haunting apparition that drifts through ancient cemeteries and desolate ruins. Its translucent, beetle-like body, with rugged, rough carapace, enhances its ghostly presence. Green, glowing eyes pierce the mist, and its twitching antennae detect metal with uncanny precision. In life, it was a terror to adventurers; in death, it is even more fearsome. It moves effortlessly through solid objects, and its rust aura corrodes metal, causing weapons and armor to crumble. This formidable foe combines the terror of its living counterpart with the dread of the undead.
Stat Block
Medium undead, neutral evil
Armor Class 17 (natural armor)
Hit Points 153 (18d8 + 72)
Speed 30 ft., fly 40 ft. (hover)
STR 16 (+3) | DEX 16 (+3) | CON 18 (+4) | INT 8 (-1) | WIS 13 (+1) | CHA 10 (+0)
Saving Throws Dex +7, Con +8, Wis +5
Damage Resistances acid, fire, lightning, thunder; bludgeoning, piercing, and slashing from nonmagical attacks
Damage Immunities cold, necrotic, poison
Senses Darkvision 60 ft., passive Perception 11
Languages understands Common but can't speak
Challenge 9 (5,000 XP)
Traits
Incorporeal Movement: The Spectral Rust Monster can move through other creatures and objects as if they were difficult terrain. It takes 5 (1d10) force damage if it ends its turn inside an object.
Ethereal Sight: The Spectral Rust Monster can see 60 feet into the Ethereal Plane when it is on the Material Plane, and vice versa.
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Rust Aura: Any nonmagical ferrous metal object within 10 feet of the Spectral Rust Monster corrodes. If the object isn't being worn or carried, it is destroyed. If the object is being worn or carried, the creature carrying it must succeed on a DC 16 Dexterity saving throw or the object takes a permanent and cumulative -1 penalty to the AC it offers or to damage rolls. The object is destroyed if the penalty reduces its AC to 10 or its damage to 0.
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Ghostly Rust: The Spectral Rust Monster's attacks bypass nonmagical armor.
Actions
Multiattack. The Spectral Rust Monster makes two attacks: one with its Antennae and one with its Bite.
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Antennae. Melee Weapon Attack: +7 to hit, reach 5 ft., one creature. Hit: The target must make a DC 16 Dexterity saving throw. On a failed save, a nonmagical metal item in the creature's possession (chosen at random) is corroded as per the Rust Aura ability.
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Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 18 (4d6 + 4) necrotic damage.
Ethereal Jaunt. Melee or Ranged Weapon Attack: +7 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 9 (1d8 + 4) piercing damage.
Reactions
Phantasmal Disappearance: When a creature within 10 feet of the Spectral Rust Monster hits it with an attack, the Spectral Rust Monster can use its reaction to turn invisible until the start of its next turn. It remains invisible even while attacking or casting spells.
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For more information on the Open Game License, please visit our OGL page.
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