The Rot Grub Hive Corpse

[Axe11154]

(First background information: In a setting im currently making, a goddess gave animals the chance to have sentience on the same level as Huminoids, but only in mass. Beast that joined groups of more then 20 would have their Intelligence raised (1 for every 20 of their own species with in 1 mile.). This effect was easiest for Insects and herd based herbivores, and as such they grew in intellect, making it difficult to farm them or exterminate them. That is why this creature is a Beast but has higher intellect.)

The Rot Grub Hive Corpse
(Volos Guide Entry) Rot grubs are finger-sized maggots that eat living or dead flesh, although they can survive on plant matter. They infest corpses and piles of decaying matter and attack living creatures that disturb them. After burrowing into the flesh of a living creature, a rot grub instinctively chews its way toward the heart in order to kill its host.
(New Entry) As rot grubs begin to swarm over corpses of the fallen they grow in mass. The blessing of Pi'āra warps their small minds into a hive like ferocity. Soon they burrow them selves into the veins of corpses and begin to puppet it like it were their own body. The corpse now home to a hive of parasites begins marching forward in search of its next meal. It will attack and inflict its self onto any it can grasp. Often with in weeks hoards of these hives will begin attaching small towns, destroying them and devouring all that get in their way. Be wary of the corpse march, for it could be a necromancers army, or a few grubs starving for their next meal.
(Art work not my own, but instead from Volos Guide.)

 

[Cleon]

(First background information: In a setting im currently making, a goddess gave animals the chance to have sentience on the same level as Huminoids, but only in mass. Beast that joined groups of more then 20 would have their Intelligence raised (1 for every 20 of their own species with in 1 mile.). This effect was easiest for Insects and herd based herbivores, and as such they grew in intellect, making it difficult to farm them or exterminate them. That is why this creature is a Beast but has higher intellect.)

The Rot Grub Hive Corpse
(Volos Guide Entry) Rot grubs are finger-sized maggots that eat living or dead flesh, although they can survive on plant matter. They infest corpses and piles of decaying matter and attack living creatures that disturb them. After burrowing into the flesh of a living creature, a rot grub instinctively chews its way toward the heart in order to kill its host.
(New Entry) As rot grubs begin to swarm over corpses of the fallen they grow in mass. The blessing of Pi'āra warps their small minds into a hive like ferocity. Soon they burrow them selves into the veins of corpses and begin to puppet it like it were their own body. The corpse now home to a hive of parasites begins marching forward in search of its next meal. It will attack and inflict its self onto any it can grasp. Often with in weeks hoards of these hives will begin attaching small towns, destroying them and devouring all that get in their way. Be wary of the corpse march, for it could be a necromancers army, or a few grubs starving for their next meal.
(Art work not my own, but instead from Volos Guide.)

Okay then, I can see a few typos in the "New Entry" section which I'll highlight amendments of in red:

As rot grubs begin to swarm over corpses of the fallen they grow in mass. The blessing of Pi'āra warps their small minds into a hive like ferocity. Soon they burrow themselves into the veins of corpses and begin to puppet it like it were their own body. The corpse, now home to a hive of parasites, begins marching forward in search of its next meal. It will attack and inflict itself onto any it can grasp. Often within weeks hordes of these hives will begin attaching small towns, destroying them and devouring all that get in their way. Be wary of the corpse march, for it could be a necromancer's army, or a few grubs starving for their next meal.​

Will comment on the statblock next.

 

[Cleon]

Okay, let's go through this in order.

Armor Class has no explanation of what the "damage threshold 11" means.

Ability array looks pretty straightforward.

Why does its Condition Immunities include petrified? Rot grubs and corpses are still mundane flesh, so why can't one petrify it?

The DC of its False Appearance feels a bit high at 16 since it's only a CR 1/4 creature.

Hold on, its Swarm Infested says that when it dies it leaves 1d3 rot grub swarms behind it. A swarm of rot grubs is a Challenge 1/2 encounter if you use the Volo's Guide to Monsters version, so one to three of them averages Challenge 1. That means it's a Challenge 1+ encounter rather than the 1/4 it's listed at.

Maybe only have it leave a single swarm of rot grubs behind it and make the hive corpse a bit meatier, so it's worth a CR of 1 or so including the swarm it leaves behind? Then its remains aren't multiple times more dangerous than its original body.

The Carrion Disease seems contrary to baseline 5E philosophy. It needs a fiddly large amount of skill checks (plus why doesn't the target get an option for CON checks?) and the healing requirements seem extortionately high for a CR 1/4 creature. After all, the Rotting Fist of a Mummy only requires a 3rd-level spell (remove curse) to cancel, and that's a supernatural curse.

 

[Axe11154]

Okay, let's go through this in order.

Armor Class has no explanation of what the "damage threshold 11" means.

Ability array looks pretty straightforward.

Why does its Condition Immunities include petrified? Rot grubs and corpses are still mundane flesh, so why can't one petrify it?

The DC of its False Appearance feels a bit high at 16 since it's only a CR 1/4 creature.

Hold on, its Swarm Infested says that when it dies it leaves 1d3 rot grub swarms behind it. A swarm of rot grubs is a Challenge 1/2 encounter if you use the Volo's Guide to Monsters version, so one to three of them averages Challenge 1. That means it's a Challenge 1+ encounter rather than the 1/4 it's listed at.

Maybe only have it leave a single swarm of rot grubs behind it and make the hive corpse a bit meatier, so it's worth a CR of 1 or so including the swarm it leaves behind? Then its remains aren't multiple times more dangerous than its original body.

The Carrion Disease seems contrary to baseline 5E philosophy. It needs a fiddly large amount of skill checks (plus why doesn't the target get an option for CON checks?) and the healing requirements seem extortionately high for a CR 1/4 creature. After all, the Rotting Fist of a Mummy only requires a 3rd-level spell (remove curse) to cancel, and that's a supernatural curse.

Nice to see you too Cleon lol.

Damage threshold is a mechanic introduced in the dmg as an official rule for vehicles. Its rarely used because vehicle combat is almost non existent. Basically this is a walking ant hill, but I wasn't sure how best to represent it out side of make its damage threshold the same as clothes AC.

Because its a swarm piloting a corpse. So it gets the same immunities as a swarm, minus the more physical ones like being knocked prone, or grappled as its alot of little worms in a single corpse.

I will be honest, I have no clue how to balance False Appearance or abilities similar to it, because its one of those things in 5e at least that arnt balanced. Lots of monsters have similar abilities where they look like one thing but aren't, and some even have it to where you cant tell them apart from their copy at all. Geonids are one such creature where if they are in their boulder form they physically cannot be told apart from any other rock and its only a CR 1/4. On the other hand you have Gas spores who cant be told apart from a beholder with out a nature check. The DC for the check is 15, HOWEVER its a nature check, one of the rarer taken skills, so just by fact players will rarely have it in their proficiencies, it makes it a much harder dc, vs the Hives Perception DC which while higher by 1, is alot more common of a skill to have and as such easier to roll.
So Yeah, I have no clue how to balance a false appearance ability, specially since it seems the ability is not connected to any stats and it just how difficult the creature is to tell from another as portrayed by the writer, and given this is a maggot infested corpse that walks, seems alot like a zombie.

Yeah I should probably bump the Cr a bit. I wasn't sure what cr to use because when using the calculator it just kept giving me the lowest of the low. CR 1 seems right though.

thats a good idea for it honestly.

Your right it should have a con save instead of a percentile chance of receiving the disease. As design philosophy, id argue its at home with the other 5e diseases, Things like Cackle Fever and Sewer Plague seem to work in a similar manor. As for the high Dc, this is kind of like the False appearance problem. Diseases dont really have cr? and as such can be kind of a weird thing to balance and seems more balanced by "How hard is this supposed tobe fore a normal person to cure, but in this case I think the big problem is just wording. The Diseases has lasting effects that are difficult to remove, and difficult to treat, however the disease its self its just trivial to cure. Any spell that heals or even lesser restoration removes the disease, its just the after effects leave your body a bit mangled. HOWEVER I gotta admit I simply worded it wrong and need togo back and freshen it up to look better because its a bit unclear how its supposed tobe cured.

 

[Cleon]

Nice to see you too Cleon lol.

Damage threshold is a mechanic introduced in the dmg as an official rule for vehicles. Its rarely used because vehicle combat is almost non existent. Basically this is a walking ant hill, but I wasn't sure how best to represent it out side of make its damage threshold the same as clothes AC.

Because its a swarm piloting a corpse. So it gets the same immunities as a swarm, minus the more physical ones like being knocked prone, or grappled as its alot of little worms in a single corpse.

Oh right.

Even so, it has a few problems.

Firstly, Damage Threshold isn't part of Armor Class, it's a special form of Damage Immunity, since it's "immune to attacks that do damage of X points of less".

Secondly, the rot grubs are piloting a decomposing corpse, so the "vehicle" is hardly the most robust in existence. The DMG does not give Rowboats a Damage Threshold, and that's a boat big enough to hold four people. I'd think a vehicle made from a humanoid body would be more fragile than a 12+ foot long wooden boat.

Thirdly, the "minus the more physical ones" mentioned above is why I think the corpse ought to be vulnerable to being petrified. Although that would not petrify the swarm inside the corpse.

 

[Cleon]

I will be honest, I have no clue how to balance False Appearance or abilities similar to it, because its one of those things in 5e at least that arnt balanced. Lots of monsters have similar abilities where they look like one thing but aren't, and some even have it to where you cant tell them apart from their copy at all. Geonids are one such creature where if they are in their boulder form they physically cannot be told apart from any other rock and its only a CR 1/4. On the other hand you have Gas spores who cant be told apart from a beholder with out a nature check. The DC for the check is 15, HOWEVER its a nature check, one of the rarer taken skills, so just by fact players will rarely have it in their proficiencies, it makes it a much harder dc, vs the Hives Perception DC which while higher by 1, is alot more common of a skill to have and as such easier to roll.
So Yeah, I have no clue how to balance a false appearance ability, specially since it seems the ability is not connected to any stats and it just how difficult the creature is to tell from another as portrayed by the writer, and given this is a maggot infested corpse that walks, seems alot like a zombie.

Well just use the default DC of 14 like a Gas Spore then.

Also, False Appearance is the wrong ability as that's the "doesn't use a DC check" one like the Mimic has.

e.g.

False Appearance (Object Form Only): While the mimic remains motionless, it is indistinguishable from an ordinary object.​

It should be Eerie Resemblance like a Gas Spore.

Oh, and the SRD suggests using Wisdom (Survival) to "Discern whether a seemingly dead or living creature is undead" so it could be that check as well as or instead of Intelligence (Nature).

 

[Cleon]

Yeah I should probably bump the Cr a bit. I wasn't sure what cr to use because when using the calculator it just kept giving me the lowest of the low. CR 1 seems right though.

thats a good idea for it honestly.

Your right it should have a con save instead of a percentile chance of receiving the disease. As design philosophy, id argue its at home with the other 5e diseases, Things like Cackle Fever and Sewer Plague seem to work in a similar manor. As for the high Dc, this is kind of like the False appearance problem. Diseases dont really have cr? and as such can be kind of a weird thing to balance and seems more balanced by "How hard is this supposed tobe fore a normal person to cure, but in this case I think the big problem is just wording. The Diseases has lasting effects that are difficult to remove, and difficult to treat, however the disease its self its just trivial to cure. Any spell that heals or even lesser restoration removes the disease, its just the after effects leave your body a bit mangled. HOWEVER I gotta admit I simply worded it wrong and need togo back and freshen it up to look better because its a bit unclear how its supposed tobe cured.

I'd just drop the disease as it already infests its victims with rot grubs which seems bad enough.

Plus it makes it simpler if there's only one ongoing effect to keep track off.

Besides, the rot grubs damage per round is a LOT nastier than the disease, and if the disease is cured magically that'd wipe out the grubs at the same time.

If I was statting up a monster based on this concept, I'd likely aim for something a good deal simpler and build it as a "two stage" monster that starts out as a single monster (the Corpse) and when its hit points are whittled down to, say, half, it becomes a Swarm as the tiny critters animating it explode out of the destroyed remains.

Heck! I'll just stat up my own take on the idea so we have something to compare the Grub Hive Corpse with…

 

[Cleon]

CORPSE WORMS

Corpse Worm Hive Cadaver
Medium monstrosity, unaligned
Armor Class 10 (natural armor)
Hit Points 22 (3d8 + 9) [its Internal Swarm has an additional 22 (4d8+4) hit points]
Speed 20 ft.

STR​	DEX​	CON​	INT​	WIS​	CHA​
11 (+0)​	6 (–2)​	16 (+3)​	3 (–4)​	6 (–2)​	5 (–3)​

Saving Throws WIS +0
Damage Resistances bludgeoning, piercing, slashing
Condition Immunities charmed, frightened, paralyzed, stunned
Senses blindsight 10 ft., passive Perception 8
Languages —
Challenge 1 (200 XP) Proficiency Bonus +2

Cadavar Shell. A corpse worm hive cadaver cannot be poisoned or diseased by physical attacks that do less than 6 points of bludgeoning, slashing or piercing damage.
 In addition, the corpse worm hive cadaver has resistance to poison and necrotic damage from attacks that do 10 points of damage or less.

Eerie Resemblance. The corpse worm hive cadaver resembles a zombie. A creature that can see the hive cadaver can discern its true nature with a successful DC 15 Intelligence (Nature) or Wisdom (Survival) check.

Internal Swarm. If a corpse worm hive cadaver is reduced to 0 hit points or petrified, a corpse worm swarm emerges from the remains and acts on the corpse worms' next turn.
 If an attack does more damage than the hive cadaver's remaining hit points, the emerging corpse worm swarm takes the excess. For example, a cadaver with 9 hit points taking 15 damage is an excess of 6, so the corpse worm swarm has 16 hit points (the swarm's 22 hit points less the 6 points of damage).

Actions

Multiattack. The corpse worm hive cadaver makes two slam attacks. If it is grappling a target, it makes a bite attack instead of its second slam attack.

Slam. Melee Weapon Attack: +2 to hit, reach 5 ft., one target. Hit: 3 (1d6) bludgeoning damage. If the target is a Medium or smaller creature, it is grappled (escape DC 12). Until this grapple ends, the hive cadaver can only attack the grappled creature.

Bite. Melee Weapon Attack: +2 to hit, reach 5 ft., one target. Hit: 1 piercing damage and the target is infested by 1d4 corpse worms. At the start of each of the target's turns, the target takes 1d6 piercing damage per corpse worm infesting it. Applying fire to the bite wound before the end of the target's next turn deals 1 fire damage to the target and kills these corpse worms. After this time, these corpse worms are too far under the skin to be burned.
 If a target infested by corpse worms ends its turn with 0 hit points, it dies as the corpse worms burrow into its heart and kill it. Any effect that cures disease kills all corpse worms infesting the target.
 If a living Medium sized creature is killed by a corpse worm infestation, the worms multiply into a swarm and transform the dead body into a corpse worm hive cadaver in 6 (1d4+4) days.


Swarm of Corpse Worms
Medium swarm of Tiny monstrosities, unaligned
Armor Class 10
Hit Points 22 (4d8 + 4)
Speed 20 ft., climb 20 ft.

STR​	DEX​	CON​	INT​	WIS​	CHA​
2 (–4)​	11 (+0)​	12 (+1)​	3 (–4)​	6 (–2)​	5 (–3)​

Saving Throws CON +3, WIS +0
Damage Resistances bludgeoning, piercing, slashing
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses blindsight 10 ft., passive Perception 8
Languages—
Challenge 1/2 (100 XP) Proficiency Bonus +2

Swarm. The swarm can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Tiny creature. The swarm can't regain hit points or gain temporary hit points.

Infest Corpse. If the corpse worm swarm spends 10 minutes burrowing into an intact Medium sized corpse that is relatively fresh (dead for 1 day or less), it transforms the corpse into a corpse worm hive cadaver piloted by the swarm.

Actions

Bites. Melee Weapon Attack: +2 to hit, reach 0 ft., one creature in the swarm's space. Hit: The target is infested by 1d4 corpse worms. At the start of each of the target's turns, the target takes 1d6 piercing damage per corpse worm infesting it. Applying fire to the bite wound before the end of the target's next turn deals 1 fire damage to the target and kills these corpse worms. After this time, these corpse worms are too far under the skin to be burned.
 If a target infested by corpse worms ends its turn with 0 hit points, it dies as the corpse worms burrow into its heart and kill it. Any effect that cures disease kills all corpse worms infesting the target.
 If a living Medium sized creature is killed by a corpse worm infestation, the worms multiply into a swarm and transform the dead body into a corpse worm hive cadaver in 6 (1d4+4) days.

Description

Vile relatives of the rot grub, a corpse worm is nigh identical in appearance but is far faster and more agile. They are communal creatures that live in self-organizing swarms. Corpse worms are active predators who constantly crave flesh, no matter how rotten it might be.
 Puppeteers of the Dead. Corpse worms have the strange ability to turn dead bodies into vehicles that offer the worms protection and a store of nourishment. A single worm that enters a fresh corpse of suitable size can breed into an entire swarm within a week or so, and the swarm then animates the body as a hive cadaver that wanders away in search of more flesh to feed on and new bodies to infest. A hive cadaver may last for several years if the worms find enough carrion to sustain the swarm, but if they find no other source of food the corpse worms will consume the cadaver within a month or two.

(Original monster designed by Cleon on the Creature Catalog Monster Homebrews forum.)