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Rust Monster

Medium · Monstrosity · CR 1/2 · Unaligned

Source. 5e 2024 Rules

14 (natural armor)

33 (6d8 + 6)

1/2

Ability Scores

Core attributes and their modifiers.

STR

DEX

CON

INT

-4

WIS

CHA

-2

Overview

Category Monsters

Size Medium

Type Monstrosity

Alignment Unaligned

XP 100

Initiative Bonus +1

Movement

Walk 40 ft (12.2 m)

Swim 20 ft (6.1 m)

Climb 20 ft (6.1 m)

Crawl 20 ft (6.1 m)

Senses

Darkvision 60 ft (18.3 m)

Passive Perception 11

Saving Throws

Strength +1 Dexterity +1 Constitution +1 Intelligence -4 Wisdom +1 Charisma -2

Traits

Iron Scent

The rust monster can pinpoint the location of ferrous metal within 30 feet of itself.

Actions

Antennae

Cost 1

The rust monster targets one nonmagical metal object—armor or a weapon—worn or carried by a creature within 5 feet of itself. Dexterity Saving Throw: DC 11, the creature with the object. Failure: The object takes a -1 penalty to the AC it offers (armor) or to its attack rolls (weapon). Armor is destroyed if the penalty reduces its AC to 10, and a weapon is destroyed if its penalty reaches -5. The penalty can be removed by casting the Mending spell on the armor or weapon.

Bite

Cost 1

+3 to hit, reach 5 ft (1.5 m). Hit: 1d8+1 piercing damage.

Melee Attack Roll: +3, reach 5 ft. 5 (1d8 + 1) Piercing damage.

Destroy Metal

Cost 1

The rust monster touches a nonmagical metal object within 5 feet of itself that isn't being worn or carried. The touch destroys a 1-foot Cube [Area of Effect]|XPHB|Cube of the object.

Multiattack

Cost 1

The rust monster makes one Bite attack and uses Antennae twice.

Reactions

Reflexive Antennae

Trigger: An attack roll hits the rust monster. Response: The rust monster uses Antennae.

About Rust Monster

Rust Monster is a medium monstrosity with a Challenge Rating of 1/2. It has a unaligned alignment.

In combat, this creature maintains an Armor Class of 14 and possesses 33 hit points (derived from 6d8 + 6).

GM Tips: Using Rust Monster

2 tips available

When using Rust Monster in your D&D 5e campaign, consider these tactical approaches:

Minion Strategy: Use as scouts or minions for larger threats
Group Tactics: Group 3-4 together to pose a moderate threat

Player Guide: Facing Rust Monster

2 strategies available

When your party encounters this creature, keep these strategies in mind:

Easy Target: This creature is weak - focus on other threats
Group Threat: Multiple can be dangerous - use area attacks

Encounter Building Calculator

Standard Party Encounter (4-5 characters):

This creature is a medium encounter for a party of 4 characters of level 1.

Solo Encounter:

A single character of level 2 (up to level 20) can face this creature in a medium to hard encounter.

Experience Point Thresholds:

Medium: 75 XP
Hard: 112 XP
Deadly: 150 XP

Based on D&D 5e Dungeon Master's Guide encounter building guidelines. CR roughly equals party level for medium encounters.

Frequently Asked Questions

What is the challenge rating of Rust Monster?: Rust Monster has a Challenge Rating of 1/2, making it appropriate for parties of level 0.5.
What type of creature is Rust Monster?: Rust Monster is a Medium Monstrosity, which affects how certain spells and abilities interact with it.