Lost Bestiary Pages #1 – The Slagrat

The Lost Bestiary Pages are monster design posts. Some random, some considered and some just for fun. Stats are generally for 5e of that popular roleplaying game that has been around a long time. Sometimes they are play tested and sometimes not. If you enjoy, please leave a comment.
Slagrat by Ben Craig, (bencraigart.tumblr.com)

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Dwajz opened the heavy door to the basement, entered and turned his lamp from side to side. The sweepings of its hazy, orange light flittering across the crates of the storeroom. The air inside the room glistened, as though impregnated with fine particles of silver. Strange enough but probably just a result of the Etherchine that had been stored here until yesterday. Dwajz didn’t like being around magic, especially not the illegal kind, but he was paid to keep eyes open and his mouth shut, which is what he did. The clanking, scratching sound rang out again. It was this that had drawn him downstairs from his watch room, where he had been trying to return to his nap.
‘Can’t an old dwarf get any peace?’ he sighed.
An hour ago, he had been woken by urchins sneaking around and testing the shuttered windows. Now he had this deal with. The dwarf moved slowly through the room. Alternating between a weary, old leg and a polished pewter stump, a consequence of a foolish adventuring youth. He made his way towards the origin of the sound. It appeared to emanate from the back, in the corner, down near the pig iron that awaited transport to Stok.
‘If wan of yae kids is in here yae betta shoe yaerself!’ He bellowed.
‘Yae’ll be gettin’ a swiff crack fraem this club if I have tae catch ya!’.
The sound stopped abruptly and Dwajz hefted his club in the air with what he hoped was menace. Grumbling softly to himself, he wobbled through crates and barrels towards the far wall. Rounding a corner, he glanced down and saw cracked bricks and dirt strewn on the floor. To the right, there was a two foot hole at the bottom of the south wall. To the left, pig iron fragments and strange oblong stones in a chaotic, jumbled mess. A heavy scent of iron, rust, dust and memory permeated the glinting air. For a second, being young in the mines around Borrinvalla.
What in hells?! Surely no round here?’ He exclaimed.
A screech echoed out from behind him. The sound of metal grinding across metal, caused him to wheel about. His lamp swung with him and illuminated a five foot high tangle of fur and glinting steel. A giant head with shining, silver eyes opened its mouth and hissed hot steam. Hard, serrated teeth shone from its maw.
‘Boreabh save me!’ He howled as the glistening thing pounced.

The pig iron was gone and Dwajz, the nightwatchman, lay in a tangled mess where it used to be. Theft most likely and the old dwarf probably stumbled upon it in progress. Still, something didn’t quite sit right with Kota. If it was theft, why did the thieves leave behind all these strange hot rocks? Why didn’t they take more valuable, lighter goods from the warehouse? Why did the air taste metallic and why in the name of the gods did they take the old dwarf’s fake leg?

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So I’m not sure where the initial idea of this monster came from. I thought I had pilfered the word slagrat from somewhere but a quick search didn’t turn up much. My brain said it might have been a slang term from Necromunda, a word for a low level ganger or something but I’m not so sure now. Anyway, wherever the word popped into my brain from I’ve now turned it into a thing, even it it wasn’t one before. Specifically, its turned into a dangerous metallic rodent monster thing for fantasy or perhaps dystopian sci-fi games. I’m generally aiming for fantasy but mutagenic substances could produce something similar in an oiled-up, macho man, desert wasteland or a sexy and fashionable, industrial-capitalist hell hole. 

So, we had two words doing a portmanteau (sort of…): Slag and Rat. The rat part provides an easy monster template and slag is related to ore processing. We could have a rat that produces slag, one that feeds on it, one that embodies its properties etc. In the end I went for one that produces slag as a ‘by-product’, an ore processing rat. Several of the traits below are a result of reading up a little on rats and ore etc. I always think a little ‘real world’ research helps get stuff going – I’m a big fan of stuff like Ballard and Atwood and how they can take something in the real and extrapolate it in their fiction. Real rats use their tails for temperature regulation so mix that with the the high temperature processes needed for purifying metals and we get the slagrat’s tails exuding extreme heat and light. The idea for variant traits is fairly obvious, if these weirdo rats eat different ores they become physically different. I tried to select metals that were reasonably commonly mined and preferably before the 1800s. That was a little tricky but still fun. It turns out that many industrial processes and isolating of elements came later than I first thought. I have tried to provide some nice context or useable info that will hopefully inspire you to put them into your games. I purposely designed three types: The slag rat, the swarm and the cannibully. This hopefully means they can be presented to adventurers at different levels rather than only provide a simple early level challenge.

The excellent artwork above is by the good pal Ben Craig. It was great to get a drawing of the beast to accompany this post and help to bring it to life. Hopefully we can do more of these in future! Anyway, without further ado-ing lets get to the beast itself.

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A writhing mass of glinting metal and thick matted fur. A monstrous fusion of rodent and warped metallic elements: Strange metallic spines, shining nodules and crystalline tumours. Serrated, saw-like incisors glint as adamantine molars crush and pound rock. Long tails glow with red-hot heat, suffusing the area in a dull crimson light. Flurried, quick movement tempered with a weight that suggests power and danger. These monstrous rodents feast on metal ores and are the origin of the powerful dwarfish curse: May slagrats find your ore before you strike it!’.

According to their brief mention in Balnarack’s Bestiary, slagrats were created by Stracian fleshcrafters in the lead up to the Tunnel War. The preparations for war required more metal than the forges could provide. The fleshcrafters proposed a solution. Careful spellworking of elemental energies would allow them to fuse giant rats and rust monsters into docile, living ore refineries. The initial experiments were successful, their creations ingested ore and excreted nuggets of pure, refined metals. However, over short generations the rats’ arcane infused bodies gradually twisted and mutated. Flesh turned slowly to metal instead of silica, heavy elements infected their clever rodent minds and the rats began to desire the metallic bounty for themselves. Hard elemental claws and teeth are not easily contained and the escapes began.

Slagrats are predominantly found underground, often in mines, where they can feed on newly discovered ore seams. Occasionally, hungry slagrats will burrow their own tunnels down from the surface, sniffing out seams beneath the earth. The tunnels and seams they uncover this way have led to some prospecting miners attempting to re-domesticate them. In underground spaces, slagrats fed on iron ore may find themselves in competition with Rust Monsters. Whilst alive the slagrats appear to be immune to the deleterious effects of rust monsters but the Rust Monsters will still happily feed on their corpses. As a result, a meeting of the two usually results in furious battle or wary retreat from each other and the area. For this reason, the two are sometimes used as pest control for each other. Outside of tunnels, caverns and mines, slagrats have been known to appear in civilised settlements. Their physical advantages mean they can easily burrow into blacksmiths, store houses of pig iron and vaults of silver and gold. There they will devour many times their weight in ore and metals before vanishing. Clearing out a slagrat infestation is no easy job. When confronted, they show little fear of conventional weaponry and fire. Social animals, they often move in large roving packs and will work together to find new food supplies. They tend to swarm densely when searching for or defending food.

A slagrat’s internal metabolism is consumed by extreme heat, they smelt, burn and refine ore, outputting the eponymous slag as waste. They will scent mark their territory with another by product, highly acidic urine that easily melts organic material. Their tails are used to help regulate this internal furnace of digestion, exuding extreme heats into the environment. This has sometimes caused fires to break out in docks and mines with a well fed slagrat infestation. Depending on the primary ores they consume, slagrats often develop unusual and often even more dangerous properties. Mercifully, their lifespans are usually relatively short. Over time, their constant ingestion of metals and ore generally causes one of two fates – shiny, metallic petrification or rarely an evolution into a giant, cannibalistic monster. Unlike most slagrats these ‘Cannibullies’ are generally found on their own, occasionally in a mating pair or even more rarely with brood of hangers on.

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Quick Reference

Underground, sometimes in settlements. Near ores or metals, surface mines, warehouses, refineries and other sites of industry.

Slagrats 6-8 (2d6). Swarms 2-3 (d3+1). Cannibullies 1-2 (d3).

A giant rat covered in metal outgrowths, its tail faintly glows with heat. Razor blade teeth glint and its eyes reflect a silvery malice.

A musky iron aroma. Rust mixed with pungent body odor and powdered stone.

Metallic scratching, and strange machine-like squeaks. A rusted wheel spinning with difficulty. The clat-pat-patter of tiny tap shoes.

Spoor (Tracking)
Staining caused highly acidic urine. Scratched floors and gnawed stone. Excreted slag forms trails of glassy stone.

Behaviour and Drive
Attack if their food or territory is threatened. Retreat when numbers fall below half. Aggressive when hungry. Swarm the weakest member of the party.

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The primary types of Slagrats that adventurers might meet are the basic Slagrat, The Swarm and the Cannibully.

Swarm of Slagrats

Slagrats can form dense groups that are more confident and even more dangerous and aggressive. This often occurs when searching for a new seam or source of food. Swarms can also be goaded by the unscrupulous to terrorise and cause damage.

Slagrat Cannibully

Cannibullies manifest in two ways. The most common is when a pack runs out of food and begins to turn on each other. One slagrat will usually end up dominant have grown in strength and stature after consuming its brood mates. Alternatively, a well fed slagrat who resists the gradual stiffening of their bodies and the metallic growths of physiology may become a cannibully. As they grow in size they start to view the ore and metal rich bodies of their fellow rats as fair game. Some tales of ancient cannibullies verge on the incredulous: they can fly, spit razersharp metal shards, have hides of interlocking metal plates like a beetle, multiple extra appendages etc. Regardless of such fanciful tales, regular cannibullies are tough, terrifying and dangerous. Some worshippers of Boreabh claim such beasts are blessed by her and do her bidding through an animalistic connection to her will. The provided stat block is for a typical individual but, if you want a more serious ancient and challenging Cannibully, you should feel free to enhance it.

Diet-Based Mutation

Roll a d10 for every four Slagrats or Swarm of Slagrats to determine their diet related traits. A Slagrat Cannibully has two of these traits.

d10MetalOre Diet / SeamSlagrat TraitSalvage / Seam Multiplier
1Iron (Fe)Pyrite, magnetite, siderite, hematite, limoniteHorned, heavy, solid and dangerous. The Iron infused slagrat has been the bane of many merchants and miners. Its charges and gores with its iron horns whilst its hide is almost impermeable. AC increases by 2. If the slagrat moves more than 10 feet before attacking it gains +2 to hit and +2 to damage on its first attack.2
2Copper (Cu)Pure Copper or ChalcopyriteCopper hairs, spiralling and thin, project at wild angles from its hide. The first time the slagrat would take fire or lightning damage on a turn it instead gains an extra action on its next turn.6
3Zinc (Zn)Sphalerite, CalamineThe skin of this slagrat is a brilliant pure white and its hair forms in wooly tufts. When the slagrat attacks a creature it destroys 1d10x100 copper coins or equivalent value in copper items by turning them into brass. In addition, a vapour-like fog is exuded from the creatures mouth. At the start of their turn, creatures within 5feet must make a Con Save (12) or be over come with Metal Fume Fever. Their movement is reduced by 5 feet as they wheeze and sputter.6
4Arsenic (As)Realgar, arcenopyrite, orpimentThis slagrat’s fur is a yellowish-green colour. A bite from this creature is highly poisonous. Con save (12) or take an addition d8 poison damage and be poisoned until taking a short or long rest.6
5Silver (Ag)Galena or chalcopyriteThe slagrat’s hide is shiny and reflective. A shimmering haze surrounds it like faintly glimpsed moonlight. When the target of a spell, there is a fifty percent chance of deflecting onto a random target within range.10
6Tin (Sn)CassiteriteThin ‘whiskers’ of tin flay off these slagrats and can cause arcing of electrical energy. If the slagrat would take lighting damage it may redirect that damage to a creature within 10 feet.4
7Antimony (Sb)StibniteThick black hair covers this slagrat while black and silver-grey bulbous growths jut from its body. Gains resistance to Acid and Lightning but gains vulnerability to bludgeoning and fire damage from all sources. When it takes bludgeoning or fire damage a fiery explosion occurs. Dex save (12) or take d8 fire damage in 5 foot radius.6
8Gold (Au)A seam of almost pure gold, Pyrite, Calaverite or SylvaniteGleaming, regal, the eyes shimmer and twinkle dazzling those who gaze upon it, just before the slagrat pounces. Such slag rats are considered especially blessed by Boreabh. The slagrat gains resistance to Acid and may cast a Cleric spell of your choice up to 1st level once per day.100
9Mercury (Hg)CinnabarThe slag rat’s body shifts and twists with ease. It is able to pour itself through small openings and reattach severed body parts. The T-1000 of heavy metal rat beasts. The slagrat may move through another creature’s space without penalty. Damage from its bite is considered poison damage and when it moves it gains 1 hp per 5 feet moved as blood and severed body parts reattach.6
10Lead (Pb)GalenaSlow, lumbering, heavy and flexible, these slagrats are the bane of magic users. The metal extruding from its skin has a dull, blue complexion and bends and flops around it. The slagrat gains advantage on saving throws against magic and is immune to thunder damage.1

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Statblocks created with D&D Statblock Generator

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A group of slagrats can be dissected for the assorted metal elements of their anatomy, along with their diamond-like teeth and claws. If a nest is discovered underground there is also a small chance (1/10) that it is near to a rich ore seam. However, a seam will require concerted mining and refining to exploit. If in a civilised land, the party may be able to claim the rights to this seam or information on its whereabouts may be sold to an interested party. A dwarf or someone with a background in mining will identify the seam easier and more accurately.

Multiply the Salvage / Seam Value by the Salvage / Seam Multiplier for metal diet of the slagrat (see table above). If a PC possesses knowledge of mining, smelting or ore, e.g. a Dwarf, they may re-roll the seam value and chance rolls.

Chance of seam: 1/10

VariantSalvage / Seam Value
Slagrat1d4 cp
Swarm of Slagrats2d8 cp
Slagrat Cannibully2d12 cp
Seamd10 gp

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Example Encounters

Below are some example encounters that may help you incorporate slagrats into your game. Slagrats don’t always need to be a monster to be fought but rather might lead to an interesting element of the story.

d12Example Encounter
1You’re in the dungeon, the slagrats are in the dungeon, you know how this one goes…
2A group of prospectors want a cargo of slagrats transported to a potential mining site to sniff out any valuable minerals.
3An arrogant mage wants to experiment on slagrats to rediscover the fleshcrafting arts used to create them. He will pay good money for live specimens.
4A number of storehouses in the dock quarter have been broken into and their contents stolen. The only clues are holes bored in the walls and strange stone lumps left behind.
5The beast of shining claw and glowing tail clangs and chimes in the dark! A village in the foothills has been beset by a terrifying monster who devours pails, ploughs, pots, pans and axes. Some have begun to worship it and leave it offerings.
6The underground river that feeds the town has been poisoned. An affliction causing confusion, headaches and in some cases death has struck its inhabitants. Some have reported strange hairy, metallic creatures disappearing into the river source. A sewer worker has gone missing only for their strangely gnawed body to appear later. Their blood had been drained of iron and flowed a pale white instead of red.
7The local dwarven mining concern has discovered a nest of slagrats and wishes them cleared. If they are not removed soon the foreman’s claim will be naught but useless slag and dust.
8The elemental plane of earth is seeping into the material. A plague of slagrats is feeding on the abundance of ores spilling into the world. Alternatively, they are following an earth elemental around and eating remnants it leaves behind.
9An underground war is taking place. Rust monsters and slagrats have been set lose by both sides. Some have made their way to the surface.
10A local noble’s pet slagrat, Terrence, has gone missing. He suspects abduction by a rival but Terrence may have heard the calling of his kin.
11A criminal gang has been running a lucrative Slagrat vs. Rust Monster fighting ring. Surely this couldn’t go wrong…
12A priest of Boreabh has been attempting to breed a Cannibully as a sign of their devotion. The local clergy will be upset if the beast is destroyed but it is also causing serious problems.

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So there we have it, the Slagrat. I enjoyed writing about it but it did take longer than I thought. Part of that was the last minute addition of the ‘flavour text’ introduction. I definitely got a bit carried away with the description etc. too. I imagine that in future these Lost Bestiary Pages might be slightly less involved but who knows. Let me know if you use it in your games, have ideas for further variants or play test it and decide its super broken. I might not do anything with that information but others might find it useful. I also hope the Page Jumps were useful for use in play. Love ya!

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