Devil, Rust

Rust Devil (Ferrugon) CR 12

XP 19,200
LE Medium outsider (devil, evil, extraplanar, lawful)
Init +5; Senses darkvision 60 ft., detect good, see in darkness; Perception +20


AC 27, touch 15, flat-footed 22 (+5 Dex, +12 natural)
hp 162 (13d10+91); regeneration 5 (good weapons, good spells, rust)
Fort +15, Ref +13, Will +10
DR 10/good; Immune fire, poison; Resist acid 10, cold 10; SR 23
Weaknesses metallic


Speed 30 ft., fly 60 ft. (good)
Melee 2 slams +19 (1d8+6), 2 wings +19 (2d6+6/17–20 plus bleed and disease)
Ranged 4 iron feathers +18 (1d6+6/19–20 plus disease)
Special Attacks bleed (1d4), disease, iron feathers, slashing wings, vainglorious whispers
Spell-Like Abilities (CL 12th; concentration +17)


During Combat In combat, a rust devil uses walls of iron to shape the battlefield to its advantage and prefers to remain adjacent to foes so it can make full attacks on them and whisper in their ears. Against foes who wield weapons, rust devils almost always use Greater Sunder to damage weapons and foes alike. If faced with foes of particularly striking appearances (often those with a Charisma score of 15 or higher), a rust devil is likely to use its flesh to iron spell-like ability, then cast shrink item on the resulting statue to keep it as a decoration for its lair.


Str 23, Dex 20, Con 24, Int 18, Wis 19, Cha 21
Base Atk +13; CMB +19 (+23 sunder); CMD 34 (36 vs. sunder)
Feats Combat Reflexes, Greater Sunder, Improved Critical (wing), Improved Sunder, Iron Will, Power Attack, Sundering Strike
Skills Bluff +21, Disable Device +21, Fly +25, Intimidate +21, Knowledge (engineering) +20, Knowledge (history) +17, Knowledge (planes) +20, Perception +20, Profession (architect) +20, Sense Motive +20
Languages Celestial, Draconic, Infernal, Terran; telepathy 100 ft.
SQ slashing wings


Disease (Ex)

Scarlet Tetanus: Iron feather or wing—injury; save: Fort DC 23; onset: immediate; frequency 1/day; effect: 1d4 Dex damage and 1 Con drain. Each time a victim takes Dexterity damage from scarlet tetanus, there is a 50% chance its jaw muscles and joints stiffen, preventing speech and the use of spells with verbal components for 24 hours; cure: 2 consecutive saves. The save DC is Constitution-based.

Flesh to Iron (Sp)

This spell-like ability functions as flesh to stone, save that it transforms the victim into iron, not stone. A victim turned to iron cannot be restored by stone to flesh, but break enchantment, polymorph any object, and similar spells can restore such a victim.

Iron Feathers (Ex)

With a flick of its wings, a rust devil can hurl a volley of four razor-sharp iron feathers at up to four targets as a standard action (make an attack roll for each feather). All targets must be within 30 feet of each other.

This attack has a range increment of 40 feet and threatens a critical hit on a result of 19–20. The rust devil’s Strength modifier applies to the damage dealt by the feathers, as if the feathers were thrown weapons. The rust devil’s feathers replenish instantly, allowing it to use this attack at will.

Metallic (Ex)

A rust devil’s iron flesh makes it susceptible to rust attacks, such as those by a rust monster or a rusting grasp spell.

Slashing Wings (Ex)

A rust devil’s wing attacks are primary attacks (except when it wields a manufactured weapon) and threaten a critical hit on a 19–20; most rust devils enhance this range to 17–20 with the Improved Critical feat.

Vainglorious Whispers (Su)

As a swift action, a rust devil can plant seeds of delusional pride in an adjacent target’s mind by whispering to it. The target can resist the influence of these whispers with a successful DC 21 Will saving throw.

On a failed save, the victim becomes overly confident in its abilities while in fact becoming less accomplished overall.

The victim gains a +4 morale bonus on saving throws against fear effects but takes a –4 penalty on all attack rolls, weapon damage rolls, caster level checks, and skill checks. The victim cannot use the withdraw action, fight defensively, cast spells defensively, take the total defense action, or use healing magic or effects on itself. It can still accept healing from other sources but must attempt saving throws to resist the effect if allowed. This is a mind-affecting, sonic, language-dependent effect, and the save DC is Charisma-based.


Environment any (Hell)
Organization solitary, pair, or company (3–7)
Treasure standard

This creature has curling ram’s horns, metallic flesh that bears coiling ribbons of rust, and wings covered with rusty metallic feathers, each resembling a weathered dagger.

A rust devil lives to sow the seeds of complacency, pride, and callous cynicism in the hearts of mortals. Also known as ferrugons, rust devils rarely attack first except when rising to defend buildings or other objects they have taken it upon themselves to protect. Rather than resorting to bloodshed, a rust devil instead seeks to bolster a mortal’s pride and to convince him to undertake works of art, construction, or craft that are likely well beyond the mortal’s skill. Nothing pleases a rust devil more than to see a mortal attempt something grand, fail spectacularly, and fall into a morass of depression, selfloathing, and jealousy for the rest of his life.

A rust devil stands only 5 feet tall but weighs 900 pounds, because of its supernaturally dense metallic flesh.

Rust devils are forged from the souls of the damned who caused pain and suffering through the application of their arts or crafts during their mortal lives. Such petitioners are often dipped repeatedly in vats of molten iron, building up layer after layer of new “flesh” that is then chiseled and forged anew by diabolic artisans.

Section 15: Copyright Notice

Mechanical Monsters © 2023, Legendary Games; Authors: Jason Nelson, Tom Phillips, Mike D. Welham, Matt Goodall, Alex Riggs, Matt Daley.

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