Creature Reference Back to Creatures

Gearmass

Large · Ooze · CR 5 · Unaligned

Source. Tome of Beasts 3

15 (natural armor)

115 (11d10+55)

Ability Scores

Core attributes and their modifiers.

STR

DEX

-3

CON

INT

-5

WIS

-2

CHA

-5

Overview

Category Monsters

Size Large

Type Ooze

Alignment Unaligned

XP 1800

Initiative Bonus -3

Movement

Walk 20 ft (6.1 m)

Swim 20 ft (6.1 m)

Climb 10 ft (3 m)

Crawl 10 ft (3 m)

Senses

Blindsight 60 ft (18.3 m)

Passive Perception 8

Skills

Perception -2

Resistances & Immunities

Damage Immunities

acid, fire

Damage Vulnerabilities

cold

Condition Immunities

blinded, charmed, deafened, exhaustion, frightened, prone

Traits

Amorphous

Move through space 1ft.+ wide with o squeezing.

Clanging Mass

Is filled with metal objects that clang scrape and clink together as it moves. When it moves it has disadvantage on Dex (Stealth) checks to stay silent until start of its next turn.

Ooze Nature

Doesn’t require sleep.

Rust Metal

Any nonmagic metal weapon that hits gearmass corrodes. After dealing damage weapon: permanent cumulative –1 penalty to damage. If penalty drops to –5 destroyed. Nonmagic metal ammo that hits gearmass destroyed after dealing damage.

About Gearmass

Gearmass is a large ooze with a Challenge Rating of 5. It has a unaligned alignment.

In combat, this creature maintains an Armor Class of 15 and possesses 115 hit points (derived from 11d10+55).

GM Tips: Using Gearmass

2 tips available

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

Aquatic Combat: This creature can swim at 20 ft. It has advantage in water environments. Consider fighting on land or using water-based spells against it.
Amorphous Movement: This creature can squeeze through spaces as small as 1 inch! Traditional barriers are ineffective. Use 'Wall of Force', 'Forcecage', or magical barriers to contain it.

Player Guide: Facing Gearmass

2 strategies available

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

Aquatic Combat Defense: This creature can swim at 20 ft! It has advantage in water. Fight on land if possible. Use 'Control Water' or drain water sources to limit its mobility.
Contain Amorphous Creature: This creature can squeeze through tiny spaces! Traditional barriers won't work. Use 'Wall of Force', 'Forcecage', or magical barriers. 'Create Bonfire' can block movement.

Encounter Building Calculator

Standard Party Encounter (4-5 characters):

This creature is a medium encounter for a party of 4 characters of level 5.

Solo Encounter:

A single character of level 7 (up to level 20) can face this creature in a medium to hard encounter.

Experience Point Thresholds:

Medium: 3,000 XP
Hard: 4,500 XP
Deadly: 6,000 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 Gearmass?: Gearmass has a Challenge Rating of 5, making it appropriate for parties of level 5.0.
What type of creature is Gearmass?: Gearmass is a Large Ooze, which affects how certain spells and abilities interact with it.