Traveler Moth Caterpillar – CR 3

Welcome to Monster Mondays! Today we present the Traveler Moth Caterpillar, the larval form of the moth possessed of a voracious and specific hunger.

Traveler Moth Caterpillar CR 3

This fuzzy many-legged arthropod is marked by powerful jaws and a starry pattern in its fur.

XP 800
Neutral Small magical beast
Init +6; Senses darkvision 60 ft., low-light vision; Perception +6


AC 15, touch 13, flat-footed 13 (+2 Dex, +2 natural armor, +1 size)
hp 31 (4d10+4);
Fort +5, Ref +6, Will +0
Defensive Abilities void immunities


Speed 20 ft., climb 20 ft.
Melee bite +5 (1d6+8 and lithotroph)
Special Attacks lithotroph


Str 14, Dex 14, Con 13, Int 2, Wis 14, Cha 10
Base Atk +4; CMB +5; CMD 17
Feats Improved Initiative, Power Attack
Skills Climb +12, Perception +6, Stealth +10, Survival +6;
SQ metamorphosis


Environment asteroids and space ships
Organization solitary, pair, or nesting ground (2-5 caterpillars and 2-5 traveler moth swarms)
Treasure none


Lithotroph (Ex)

The caterpillar does double damage with its bite attack against any non-organic creature or construct. When the caterpillar successfully damages a creature wearing non-organic armor, it also deals the listed damage to the creature’s armor. The caterpillar’s natural weapons ignore damage reduction as if they were adamantine.

Metamorphosis (Ex)

Upon death there is a 50% chance that a traveler moth swarm will burst from the corpse of a traveler moth caterpillar. The swarm will immediately attempt to kill the creature that destroyed its former body.

If a caterpillar is allowed to fully mature, the caterpillar body will die and be transformed into a traveler moth swarm.

Void Immunities (Ex)

The traveler moth caterpillar can survive in the void of space without suffering any damage or negative conditions from decompression, radiation, or lack of breathable air.

The traveler moth caterpillars are a plague upon space travel and asteroid mining. While the moths themselves are in themselves relatively harmless, they have an uncanny ability to seek out deposits of metal, in a raw or processed form. They then lay eggs which sprout and quickly grow into large caterpillars that quickly devour all metal that they can find on the asteroid and ship they are born on, before finally transforming and bursting into a new swarm of moths to find new feeding grounds.

Left unopposed, a group of caterpillars can quickly strip an asteroid or ship clean of all metal deposits and components, at best ruining a mining claim, and at worst opening a ship up to the void of space.  Voracious eaters, the caterpillars will consume any metal they can find, including the razor wings of the moths who birthed them, the corpses of their parents often the first meal that any caterpillar consumes.

Possessing little of the intelligence or magical abilities of the moths that they later become, the caterpillars are nearly mindless, trying to consume all metal that they can, as quickly as they can, trusting on their natural toughness to avoid getting killed by the side effects of their voracious appetites.

As they reach their full size, more and more of their bodies resources are put towards metamorphosis, as a large number of razor-winged traveler moths are formed underneath their outer skin, ready to burst out upon the moment of death to colonize a new home and breed a new generation of caterpillars. Unlike most metamorphosing creatures, a single fully grown caterpillar can give transform into hundreds of distinct moths, though given their hive-like mentality, it is unclear if the moths born are truly a distinct entity, or simply the limited consciousness of the caterpillar taking on an expanded form.

Hunted by the Shaman Knights as a deadly scourge, their transport, and use is prohibited in all of civilized space. Nonetheless, the caterpillars have found some use in warfare and sabotage, the clandestine planting of eggs a particularly effective way to destroy a military installation from the inside.

About Kevin Bryan

Kevin Bryan is a monster writer for the Open Gaming Network, and is looking forward to bringing all sorts of strange and bizarre creatures to life. His personal website is

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