Monster Mayhem
Crystal Beetle Swarm
By Eric Cagle

"Well," said Fira to no one in particular, "it seemed like a good idea at the time." The nausea was slowly fading, allowing her to take stock of the situation. A few minutes before, she had stepped through the strange portal back in the Tower of Ankurra, thinking that it would lead to another part of the fortress that she had already infiltrated. Much to her surprise, the circular obsidian archway did not open up into the inner sanctum. Instead, the sunrod in her hand revealed that she was in a large cave, with several tunnels leading off into darkness. Behind her, where the archway should have been, stood a sheet of smooth marble.

She had no idea where she was; the portal had sent her . . . somewhere. She could not even begin to guess where "somewhere" was. Fira made a mental note to stick a blade -- no, two -- into the fat belly of that gnome who had provided her with the map of the Tower of Ankurra. He was probably in their employ and she scolded herself for being so gullible.

She searched in the gloom for almost an hour, trying to ascertain whether the portal was still there. Her hand smacked nothing but solid rock. "Ah, Olidamarra," Fira chuckled. "You must be laughing at me right now." Finding nothing of note, she picked one of the tunnels at random and slowly crept through the darkness. The tunnel dipped and curved without warning -- it looked natural, but she could make out telltale signs of the stone being worked. It had an odd texture, however, as it if had been chewed out. Great. Who knows what could be down here?

Fira lost track of how long she had wandered through the tunnel. Her knees were scraped and bloody; her head throbbed from the numerous times she cracked it against a low overhang. A low rushing sound, like a waterfall was barely perceptible in the depths of the tunnel. Emboldened at the thought of finding an underground river that she might be able to navigate, Fira pressed on.

The rushing sound grew louder and all around her. She paused in confusion: Unless she was wrong, she should have reached the water by now. She sat down, exhaustion and a rising sense of panic beginning to overtake her. She was lost, hungry, and thirsty . . . and water was somewhere nearby.

Something had burrowed through the tunnel behind her and plopped onto her armor. She jumped and swatted it away. In the bright glare of the sunrod, it looked like a beautiful diamond. She instinctively reached down to pick up the gem, when it suddenly sprouted legs and scurried toward her. She shrieked and drew her sword in a flash. A moment later, she knew what the source of the rushing noise was. A torrent of gemlike beetles poured from a hole in the wall, leaving behind a slick, glassy layer on the surface of the stone. Fira dropped the sunrod and slashed wildly at the swarm as it crawled up her legs. She turned to run back up the tunnel she'd come from, but found herself rooted in place, her feet encased in the same crystalline substance. Her sword flailed around without effect until the swarm of crystal beetles reached her arms and froze them in place. Fira's screams ended moments later when her head was finally encased.

Fira could see perfectly through the clear crystal, though she couldn't tell that the swarm had stopped moving after it finished entombing her. For a few fleeting seconds, Fira thought that she could crack out of the layer -- until intense burning consumed her. Even had someone been standing beside her, Fira's last screams could not have been heard through the crystal that slowly dissolved her into an indistinct mush.

Crystal Beetle
Medium-size Vermin (Earth, Swarm of Fine Creatures)
Hit Dice: 9d8+27 (67 hp)
Initiative: +0
Speed: 30 ft., burrow 30 ft.
AC: 19 (+9 natural), touch 10, flat-footed 19
Base Attack/Grapple: +6/ --
Attack: Swarm
Full Attack: Swarm
Damage: Swarm 2d6 plus 2d6 acid
Face/Reach: 5 ft./0
Special Attacks: Encase, distraction (DC 16)
Special Qualities: Acid immunity, Swarm traits, tremorsense, vermin traits
Saves: Fort +9, Ref +3, Will +3
Abilities: Str 1, Dex 10, Con 16, Int -- , Wis 10, Cha 2
Climate/Terrain: Any land and underground
Organization: Solitary or army (10-40 swarms)
Challenge Rating: 6
Treasure: None
Alignment: Always neutral
Advancement: --

Crystal beetles are ubiquitous fist-sized vermin that primarily dwell on the Plane of Earth. They fulfill a similar ecological niche as many other burrowing insects do on the Material Plane -- churning through rock and turning it into rich soil. Their name derives from their crystal-like carapace, which shines and scintillates on the rare occasions when light shines upon them. It is transparent, allowing the viewer to see the organs inside the beetle's body. The shell of a crystal beetle is made from a hard, transparent substance that resembles a diamond or rock crystal. Some swarms find their way to the Material Plane, where they will happily feast on veins of ore and gems, as well as any hapless creatures that blunder into their path. Certain creatures native to the Plane of Earth, such as xorns and umber hulks, find crystal beetles delicious (if dangerous) food and gorge on swarms when they find them.

Crystal beetles feed upon stone, earth, and gemstones. To help them digest such tough matter, they exude a crystalline substance that releases a powerful acid. In a matter of minutes, the stone is reduced to a more palatable goo that they feast upon. Crystal beetles apparently have a "sweet tooth" when it comes to living creatures -- a swarm of crystal beetles will overrun a creature, encase it in crystal, and feed upon the remains. Such a rare treat will draw nearby swarms, which will completely cover the victim in hope of gaining a taste. The sound of a crystal beetle swarm burrowing through the stone sounds like a rush of water.

Despite its resemblance to gemstone, the crystal beetle has no value other than as a curiosity. If a lone beetle becomes separated from the rest of the swarm, it dies in 1d6 days and slowly disintegrate from its own internal acid (causing no damage).


Crystal beetles attempt to overrun a creature and encase it in a crystal. The swarm surrounds its target for at least three rounds, creating a very thick layer, before waiting for the acid to reduce the victim to mush.

Vermin Traits: A crystal beetle swarm is immune to all mind-affecting effects (charms, compulsions, phantasms, patterns, and morale effects). It also has darkvision (60-foot range).

Swarm Traits (Ex): Not subject to critical hits or flanking. Immune to mind-affecting spells. Immune to damage from all weapons. Immune to single-target spells. Vulnerable to area effects. Does not threaten nearby squares.

Distraction (Ex): Any nonmindless creature vulnerable to the swarm's damage that begins its turn with a swarm in its square is nauseated for 1 round; a Fortitude save (DC 16) negates the effect. Spellcasting or concentrating on spells within the area of a swarm requires a Concentration check (DC 20 + spell level). Using skills involving patience and concentration requires a Concentration check (DC 20).

Acid (Ex): The swarm attack of a crystal beetle swarm deals 2d6 points of acid damage in addition to the normal damage of its bite.

Encase (Ex): A crystal beetle swarm has the ability to encase a creature in a crystal-like substance that breaks down its victim with acid. A creature that has been swarmed for two consecutive rounds must make a Reflex save (DC 17) encased in a layer of tough, crystal-like substance exuded from the crystal beetle swarm. The encased creature is held motionless, unable to move or attack, until it escapes. An encased creature can make a Strength check (DC 15) to break out of the layer and takes no acid damage that turn if successful. An ally can break loose an encased creature, with a Strength check (DC 20); the material proves slightly easier to break from the inside (a matter of leverage). Each additional round of encasement thickens the layer, increasing the Break check DC by +5 per additional round.

The crystal-like substance releases acidic enzymes that cause 2d6 points of acid damage per round to the creature trapped inside. Once the creature is reduced to -10 hit points, it completely dissolves into pinkish mush. The crystal beetles then burrow through the encased layer to feast upon the remains. In addition, the encased creature begins to suffocate after 2 rounds (see the Drowning Rule in Chapter 3 of the Dungeon Master's Guide).

Swarm Traits: A swarm has no clear front or back and no discernible anatomy, so it is not subject to critical hits or flanking. A swarm made up of Tiny creatures takes half damage from slashing and piercing weapons. A swarm composed of Fine or Diminutive creatures is immune to all weapon damage.

Reducing a swarm to 0 hit points or fewer causes the swarm to break up, though damage taken until that point does not degrade its ability to attack or resist attack. Swarms are never staggered or reduced to a dying state by damage. Also, they cannot be tripped, grappled, or bull rushed, and they cannot grapple another.

A swarm is immune to any spell or effect that targets a specific number of creatures (including single-target spells such as disintegrate), with the exception of mind-affecting effects if the swarm has an Intelligence score and a hive mind. A swarm takes a -10 penalty on saving throws against spells or effects that affect an area, such as many evocation spells or grenadelike weapons. If the area attack does not allow a saving throw, a swarm takes double damage instead.

Swarms made up of Diminutive or Fine creatures are susceptible to high winds such as that created by a gust of wind spell. To determine the effect of wind on a swarm, treat the swarm as a creature of the same size as its constituent creatures. For example, a swarm of Abyss ants (Diminutive creatures) can be blown away by a severe wind. Wind effects deal 1d6 points of subdual damage to the swarm per spell level (or Hit Die of the originating creature, in the case of effects such as an air elemental's whirlwind). A swarm that takes subdual damage sufficient to exceed its current hit points becomes disorganized and dispersed, and does not re-form until its current hit points exceed its subdual damage.

Tremorsense (Ex): A crystal beetle swarm can automatically sense the location of anything within 60 feet that is in contact with the ground.

About the Author

Eric Cagle is a freelance game designer who works for the Organized Play Department at Wizards of the Coast. Recent credits include the Arms and Equipment Guide, Fiend Folio, Urban Arcana, and design work for the Star Wars Roleplaying Game. He's a frequent contributor to both Dragon magazine and the Wizards of the Coast website.

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