---
obsidianUIMode: preview
cssclasses: json5e-monster
tags:
- compendium/src/5e/mm
- monster/environment/underdark
- monster/size/medium
- monster/type/monstrosity
aliases: ["Rust Monster"]
---
# Rust Monster
*Source: SRD / Basic Rules*  

```ad-statblock
title: Rust Monster
![](compendium/bestiary/monstrosity/token/rust-monster.png#token)
*Medium monstrosity, Unaligned*

- **Armor Class** 14  (natural armor)
- **Hit Points** 27 (`5d8 + 5`)
- **Speed** 40 ft.

|STR|DEX|CON|INT|WIS|CHA|
|:---:|:---:|:---:|:---:|:---:|:---:|
|13 (+1)|12 (+1)|13 (+1)| 2 (-4)|13 (+1)| 6 (-2)|

- **Proficiency Bonus** +2
- **Saving Throws** ⏤
- **Skills** ⏤
- **Senses** darkvision 60 ft., passive Perception 11

- **Languages** —
- **Challenge** 1/2

## Traits

***Iron Scent.*** The rust monster can pinpoint, by scent, the location of ferrous metal within 30 feet of it.

***Rust Metal.*** Any nonmagical weapon made of metal that hits the rust monster corrodes. After dealing damage, the weapon takes a permanent and cumulative −1 penalty to damage rolls. If its penalty drops to −5, the weapon is destroyed. Non magical ammunition made of metal that hits the rust monster is destroyed after dealing damage.

## Actions

***Bite.*** *Melee Weapon Attack:* +3 to hit, reach 5 ft., one target. *Hit:* 5 (`1d8 + 1`) piercing damage.

***Antennae.*** The rust monster corrodes a nonmagical ferrous metal object it can see within 5 feet of it. If the object isn't being worn or carried, the touch destroys a 1-foot cube of it. If the object is being worn or carried by a creature, the creature can make a DC 11 Dexterity saving throw to avoid the rust monster's touch.

If the object touched is either metal armor or a metal shield being worn or carried, it takes a permanent and cumulative −1 penalty to the AC it offers. Armor reduced to an AC of 10 or a shield that drops to a +0 bonus is destroyed. If the object touched is a held metal weapon, it rusts as described in the Rust Metal trait.
```
^statblock

## Environment

underdark