Why are swarms excluded from various transformation and befriending options?

[Segev]

Wild shape, polymorph, conjure animals... whenever a tool lists what they can turn things into or call up, swarms are excluded. I can't find the rules that say they should be, but assuming they areas why?

Are swarms that powerful? What would be a reasonable resource investment to be able to control or transform into swarms? A feat? A magic item <of what rarity)? The Swarmkeeper Ranger is not only limited to Rangers only, but doesn't really yield a swarm you can control so much as some battlefield movement and a minor bit of telekinesis.

So, why the limit? If the limit is not RAW, why is it assumed?

[JNAProductions]

I don't think it's a balance thing-it's a lore thing. You can turn into ONE animal with the right magic or what-have-you. But it's much harder to turn into a hundred animals at once.

[Mastikator]

I don't think it's a balance thing-it's a lore thing. You can turn into ONE animal with the right magic or what-have-you. But it's much harder to turn into a hundred animals at once.

This.

But I would like to see summoning of swarms, instead of summoning of multiple creatures anyway.

[ciopo]

The traditional swarm summoning spell in 3.5 was insect plague, but that got changed to be direct damage im 5e

[Segev]

Would it break anything for Conjure Animals to call forth Swarms of the correct CR?

[JackPhoenix]

Would it break anything for Conjure Animals to call forth Swarms of the correct CR?

It would be kinda weird to be able to summon either 8 spiders or 4 entire swarms of (presumably the exactly same) spiders with the same spell, but nothing in between. Summon Swarm used to be its own spell, though....

[Amnestic]

It won't 'break' anything but they may prove to be more resilient assuming there's nothing deploying AoE. Swarm of Rats has a decent health pool, plus resistant to all BPR (and a slew of condition immunities).
On the other hand, they can't box in creatures like a herd (not a Swarm) of cows can, and with generally below average attack rolls there's more incentive for a character to just run past the swarm and hit the caster in the face instead. Swings and roundabouts.

Personally I'd steer away just because it marginally complicates damage roll numbers by tracking health (as opposed to "is it alive->it does this amount of damage on a hit") and CA doesn't need more complexity as standard.

[Unoriginal]

Wild shape, polymorph, conjure animals... whenever a tool lists what they can turn things into or call up, swarms are excluded. I can't find the rules that say they should be, but assuming they areas why?

Are swarms that powerful? What would be a reasonable resource investment to be able to control or transform into swarms? A feat? A magic item <of what rarity)? The Swarmkeeper Ranger is not only limited to Rangers only, but doesn't really yield a swarm you can control so much as some battlefield movement and a minor bit of telekinesis.

So, why the limit? If the limit is not RAW, why is it assumed?

Swarms are mechanically distinct from Beasts in a number of ways.

Presumably, the devs just didn't want to deal with the hurdles players-accessible Swarms would create.

Ex: sending all the creatures of the Swarm in melee except one that stay safely on teammate's shoulder means someone Polymorphed into a Swarm has nothing to fear.

[Mastikator]

Would it break anything for Conjure Animals to call forth Swarms of the correct CR?

If anything it would be preferable, specifically if you could just summon bigger swarms with upcasting that could attack multiple-er targets. No more 16 snakes please, swarm of snakes and upcast = bigger swarm of snakes. (or whatever animal the player prefers, bears, stampede of rhinos, I dunno)

[Goobahfish]

I made a druid subclass to basically enable this. Swarm Druid.

Was very fun. Wasn't overpowered by any means so, I think it just that it is 'weird' is the main issue.

[NecessaryWeevil]

It would be kinda weird to be able to summon either 8 spiders or 4 entire swarms of (presumably the exactly same) spiders with the same spell

Why would you need to assume they are the same kind of spiders?

[OldTrees1]

Why are swarms excluded from various transformation and befriending options?


The more creative and abnormal the idea, the less likely the authors thought of it. There is nothing wrong with transforming* into, summoning**, or befriending*** a swarm, but it was not something the authors thought of.

* Remember all the stories questioning what happens mentally if you transform into another creature? Often it is toned down to you inheriting helpful mental patterns (know how to fly) but not inheriting neutral (that fly looks tasty) or detrimental (forgetting) patterns. Consider what it would be like to be 100s of individual minds that happen to be working together based on coordinating instincts. Interesting but complicated, so perfect for an RPG.

** Summoning a swarm means controlling 100s of individual creatures. It helps that their instincts are keeping them coordinated, but one size fits all commands might take finesse to translate to the swarm without disrupting the swarming behavior. Sounds interesting to me.

*** Compare befriending a human to befriending a mob of humans. It is similar but not quite the same thing. I expect befriending a swarm would be similar. Sounds interesting.

[Unoriginal]

The more creative and abnormal the idea, the less likely the authors thought of it. There is nothing wrong with transforming* into, summoning**, or befriending*** a swarm, but it was not something the authors thought of.

* Remember all the stories questioning what happens mentally if you transform into another creature? Often it is toned down to you inheriting helpful mental patterns (know how to fly) but not inheriting neutral (that fly looks tasty) or detrimental (forgetting) patterns. Consider what it would be like to be 100s of individual minds that happen to be working together based on coordinating instincts. Interesting but complicated, so perfect for an RPG.

** Summoning a swarm means controlling 100s of individual creatures. It helps that their instincts are keeping them coordinated, but one size fits all commands might take finesse to translate to the swarm without disrupting the swarming behavior. Sounds interesting to me.

*** Compare befriending a human to befriending a mob of humans. It is similar but not quite the same thing. I expect befriending a swarm would be similar. Sounds interesting.

They thought about it, they just decided it was too much of a bother to calibrate for player use.

A Swarm is inherently more versatile than an equivalent-CR Beast.

Same reason there are no "Summon Humanoid NPC" spells in the books (closest being the oft-discussed Simulacrum).

[Segev]

They thought about it, they just decided it was too much of a bother to calibrate for player use.

A Swarm is inherently more versatile than an equivalent-CR Beast.

Same reason there are no "Summon Humanoid NPC" spells in the books (closest being the oft-discussed Simulacrum).

Could you elaborate on this? I am not s saying you're wrong, but I do not see where you're coming from to justify these claims. Again, this isn't, "You're wrong!" so much as "Why are you right?"

[Unoriginal]

Could you elaborate on this? I am not s saying you're wrong, but I do not see where you're coming from to justify these claims. Again, this isn't, "You're wrong!" so much as "Why are you right?"

The way I see it:

The devs have no problem with PCs summoning, controlling or transforming into a CR 2 Polar Bear. None of this applies to a CR 2 Swarm of Poisonous Snakes.

The Swarm has less HPs, fewer and less reliable attacks, less reliable damage (including an easily-passed save and an oft-resisted damage type for the rider, and doing less damage when hurt), and can't heal.

On the other hand, it has resistance to B/P/S (something the devs always considered super-valuable for a PC), immunity to 8conditions (ditto), and the capacity to occupy other creatures' space without any requirement or penalty (something the devs have been *very* shy about giving to PCs), not to mention blindsight and the capacity to go through Tiny spaces without issues (two things that the devs rated highly still, if not as valuable as the rest).

Do you agree with those points so far?

[OldTrees1]

They thought about it, they just decided it was too much of a bother to calibrate for player use.

A Swarm is inherently more versatile than an equivalent-CR Beast.

Same reason there are no "Summon Humanoid NPC" spells in the books (closest being the oft-discussed Simulacrum).
A swarm is differently versatile than an equivalent CR beast. I would not say it is inherently more versatile given its decreased ability to manipulate the world physically (although your analysis is probably deeper and more accurate than mine). Consider a CR 1 swarm of spiders (upscaled from CR 1/2) vs a CR 1 giant spider. The former has better maneuverability due to amorphous shape, the latter can do crowd control with webs and its solid body (and carry passengers).

I agree they decided not to bother. However I think that included not bothering thinking about it. Since they are focusing on the core, a lot of things are afterthoughts they never get around to thinking about. Or once they do get around to thinking about them, they already made it too much of a bother.

For example:

Ex: sending all the creatures of the Swarm in melee except one that stay safely on teammate's shoulder means someone Polymorphed into a Swarm has nothing to fear.
We have different assumptions: The swarm is in melee. The "one" is not part of the swarm any more. Someone polymorphed into a swarm stays with the swarm, not with the bugs that leave the swarm.

Edit:

~elaborating~

Do you agree with those points so far?

Seems good so far. Swarms are more resilient (taking in the immunities and resistance) but lower offense? Their swarm body has advantages and disadvantages arising from its amorphous flowing shape? Swarms gaining blindsight (snakes vs swarm of snakes) surprised me, but is a bit hit or miss. Bats & spiders already had it. Swarms of ravens & rats don't gain it.

[Goobahfish]

They thought about it, they just decided it was too much of a bother to calibrate for player use.

A Swarm is inherently more versatile than an equivalent-CR Beast.

Same reason there are no "Summon Humanoid NPC" spells in the books (closest being the oft-discussed Simulacrum).

Whether or not a swarm is more versatile than a bear is an argument that can be had. However, I think it is definitely true that being able to transform/summon a swarm and a bear is more versatility than summoning a bear and an elk for example. The swarm definitely has some capabilities which are very 'different' from all other choices.



We have different assumptions: The swarm is in melee. The "one" is not part of the swarm any more. Someone polymorphed into a swarm stays with the swarm, not with the bugs that leave the swarm.

Herein lies the 'actual reason' for swarms not being part of the summon/wildshape abilities. (Or at least, based on my design experience, this is where it lies).

There are two main issues.
#1: The mechanical limitations. When a DM controls a swarm, it is usually just a HP blob with some 'complications' added. However, when a player controls a swarm, there are a lot of 'extra hidden rules' which need to be adjudicated. Can the swarm split? How much can the shape of the swarm change? Can a swarm lift objects? Can it pick a lock?

The answers to most of these questions are not 'obvious'. At least, not as obvious as 'can a bear lift up this log?'.

#2: The metaphysical limitations. This is more particular to the Wildshape version. When a character transforms into a swarm... where are they? This is a rather complex question as a swarm of insects is very different from a 'I turn into a bird' if only because there aren't many fictional examples of non-villainous (i.e., non-POV) characters transforming into a swarm of insects/rats/birds etc.

If we consider what we normally expect when fighting a swarm (we are slowly killing the members, one by one) that is qualitatively different from beating an ox to death and having it spontaneously fall back into human form. The fiction here is that 'when you squash the last bug'... what?

Hence, I suspect the designers were like... oh... too many words. Too much 'what-if'.

Tangent time

For my D&D swarm-druid, it wasn't really a big issue, but when designing my own RPG, I was really set on conceiving as to what the skill school associated with 'swarminess' was. For example, can a swarm person transform into a swarm of spiders or a swarm of rats? That seemed very thematically diverse. What was the largest creature for example. In the end I went with a variation on the term 'Egregore' which is this kind of spiritual unconscious between beings, which, interestingly enough then meant the skill could have techniques from 'swarm of tiny critters' to 'create clone of self' or 'turn into two small dogs' etc. It was more about splitting the unconscious than actually the swarm-forms.

[elyktsorb]

As someone who played 4th edition, 4th edition had a version of druid that could turn into swarms and it was super ****ing cool

[OldTrees1]

As someone who played 4th edition, 4th edition had a version of druid that could turn into swarms and it was super ****ing cool

^ This is why these "too much bother" areas of the game are worth designing.

3E had a couple. I did not try them, but I presume they were cool.

Does anyone know, did AD&D have a swarm druid?

[Witty Username]

I don't think it's a balance thing-it's a lore thing. You can turn into ONE animal with the right magic or what-have-you. But it's much harder to turn into a hundred animals at once.

This is probably the reason, back in the day swarms were immune to weapon damage (congrats you skewered a spider, what about the other hundred), and had penalties to AoE damage and saves against such, for similar reasons.

[Joe the Rat]

I made a druid subclass to basically enable this. Swarm Druid.

Was very fun. Wasn't overpowered by any means so, I think it just that it is 'weird' is the main issue.

This is where it ought to be - and ought to have been done by wotc. Hell, the swarmkeeper ranger ought to have a swarm statblock available for their conjuring options.
I totally see swarm transformation as a specialty like this, particularly since you can use the Circle features to "balance" any issues.


Leaning back to 3e options, a "turn into a swarm of bats (or ravens or butterflies or angsty starlings) and skedaddle" Warlock invocation would be fair game.

[Segev]

Swarms in 5e have a bunch of immunities, but they're not the sort of immunities that make a PC or a PC's pet untouchable. They don't have the mass of special rules 3e did, and they occupy a defined space, so "splitting off" parts either does nothing or makes them lose hp, not lets them leave things lying around to keep "part of themselves" active. Most aren't even hive minds (though I suppose the note on swarms suggests there is magic holding any that are acting as a swarm stat block together).

I'm seriously wondering if just assuming that you CAN, in fact, polymorph into, wild shape into, or conjure up swarms of the kinds of creatures your features and spells can call forth would actually be a problem. Heck, I still am not sure the rules don't allow it, as written; the only evidence against it I can find is the third party tools' tendency to specifically exclude swarms from sorted lists of options for those features. A swarm of rats in the MM is one creature and has the beast type and a CR low enough to polymorph into, conjure with conjure animals, or wild shape into. Is there a rule printed somewhere I am missing that explicitly excludes swarms, or a combination of rules that implicitly does? And, either way, would it be broken to allow swarms as if they were their creature type with their listed CR, after all?

[Amnestic]

I'm seriously wondering if just assuming that you CAN, in fact, polymorph into, wild shape into, or conjure up swarms of the kinds of creatures your features and spells can call forth would actually be a problem. Heck, I still am not sure the rules don't allow it, as written; the only evidence against it I can find is the third party tools' tendency to specifically exclude swarms from sorted lists of options for those features. A swarm of rats in the MM is one creature and has the beast type and a CR low enough to polymorph into, conjure with conjure animals, or wild shape into. Is there a rule printed somewhere I am missing that explicitly excludes swarms, or a combination of rules that implicitly does? And, either way, would it be broken to allow swarms as if they were their creature type with their listed CR, after all?

A swarm of rats is not one creature, it is a grouping of many creatures into a swarm.

Sage Advice Compendium:

Can conjure animals summon a swarm?
No. Conjure animals summons individual creatures, and swarms are groups of creatures.

MM 337's Nature of Swarms also specifies it is more than one creature:-

The Nature of Swarms
The swarms presented here aren't ordinary or benign assemblies of little creatures.
They form as a result of some sinister or unwholesome influence. A vampire can summon swarms of bats and rats from the darkest corners of the night, while the very presence of a mum my lord can cause scarab beetles to boil up from the sand-filled depths of its tomb. A hag might have the power to turn swarms of ravens against her enemies, while a yuan-ti abomination might have swarms of poisonous snakes slithering in its wake. Even druids can't charm these swarms, and their aggressiveness is borderline unnatural .


Polymorph/WS specify that you change into one creature. Swarms are multiple creatures grouped into a single statblock.

Again, you might not break anything by allowing such transformations or summons (though I think swarms are potent enough that they might become a staple option due to resistances/immunities) but they're pretty set on you not doing so as standard, likely for the reasons provided above in the thread.

Personally I agree with others who suggested a subclass feature is the way to go to allow it.

[Theodoxus]

Ex: sending all the creatures of the Swarm in melee except one that stay safely on teammate's shoulder means someone Polymorphed into a Swarm has nothing to fear.

This was my first thought on reading the title of the thread. Not to mention, when / if that last bug is killed (say, the teammate gets caught in a fireball), where does the druid's body appear? Where the majority of the mass is? Where the last bug died? Not insurmountable questions, but ones that should be addressed before going down this route. Secondarily, how many HP does that last bug have? 1? And so nigh all the damage that kills that one bug carries to the druid? Seems hazardous in the extreme... in universe, I suspect that would be a big deterrent taught in Druid School "The cautious tale of ArchDruid Furry McFuzzyFace who learned to become a swarm of rats and died an excruciating death when the last of him was swallowed by the Dire Wolf of Brighton Moor"


We have different assumptions: The swarm is in melee. The "one" is not part of the swarm any more. Someone polymorphed into a swarm stays with the swarm, not with the bugs that leave the swarm.


That's a decent rule to go with, but steps all over player agency. I know if I had the option to become a swarm (even after the cautionary tale of Furry), I'd want to make do with all the shenanigans I could. Saying my fingernail that stayed behind becomes my fingernail again when the rest of my swarm body moves off is... poopy.

[Segev]

This was my first thought on reading the title of the thread. Not to mention, when / if that last bug is killed (say, the teammate gets caught in a fireball), where does the druid's body appear? Where the majority of the mass is? Where the last bug died? Not insurmountable questions, but ones that should be addressed before going down this route. Secondarily, how many HP does that last bug have? 1? And so nigh all the damage that kills that one bug carries to the druid? Seems hazardous in the extreme... in universe, I suspect that would be a big deterrent taught in Druid School "The cautious tale of ArchDruid Furry McFuzzyFace who learned to become a swarm of rats and died an excruciating death when the last of him was swallowed by the Dire Wolf of Brighton Moor"



That's a decent rule to go with, but steps all over player agency. I know if I had the option to become a swarm (even after the cautionary tale of Furry), I'd want to make do with all the shenanigans I could. Saying my fingernail that stayed behind becomes my fingernail again when the rest of my swarm body moves off is... poopy.

I don't think it steps on player agency to have the player declare where his character is, and have that be where the swarm counts as being. Swarms occupy a particular space. That's where whoever the swarm is, is.

If you detach an individual member of the swarm, it is no longer part of "you." This may have no mechanical effect, or it may cost you hp, but it isn't going to make you exist in two places.

[stoutstien]

IMO swarm is a description of behavior patterns as much as a physical make-up. I can't just shove a bunch of the same type of creatures into a small space and it becomes a swarm. same for flocks, herds, schools, or shoals. The collection needs to to have some form of heuristic group think that takes priority over individuals in it.

When you have 2 or more things that are functioning independently but still towards a similar goal I'd say that's a pack type grouping.

[OldTrees1]

That's a decent rule to go with, but steps all over player agency. I know if I had the option to become a swarm (even after the cautionary tale of Furry), I'd want to make do with all the shenanigans I could. Saying my fingernail that stayed behind becomes my fingernail again when the rest of my swarm body moves off is... poopy.

Hmm, the way I pictured it, if a bug leaves the swarm, that is not "your fingernail" leaving. You wildshaped into the swarm and thus new bugs can join you and old bugs can leave you. You are not leaving your fingernail behind. You emerge intact from the swarm when the swarm is disrupted (swarm drops to 0hp despite still having the majority of the bugs when the critical cohesion was lost).

I am not sure it steps on player agency. Swarms are defined by the population exhibiting swarming behavior. You can still do all the shenanigans a swarm can. You just can't do any of the shenanigans a large population of independently acting individuals can*.

*That is what wildshaping into a two headed, two tailed, bifurcated snake is for. To be fair, multibody wildshape (in contrast to swarm wildshape) is much more complicated to calibrate for PC use and is an even smaller niche. However it also sounds interesting.

[Goobahfish]

I don't think it steps on player agency to have the player declare where his character is, and have that be where the swarm counts as being. Swarms occupy a particular space. That's where whoever the swarm is, is.

If you detach an individual member of the swarm, it is no longer part of "you." This may have no mechanical effect, or it may cost you hp, but it isn't going to make you exist in two places.

I think this is broadly right. As I said earlier, the main issue is that the 'intuitions' here are difficult and swarms are different enough to need at least a paragraph of clarifications when compared to other creatures (hence the omission).

IF, the swarm is treated as a glorified beast blob then there are literally no gameplay issues (it is hardly overpowered). Nothing gets weird and I think there should be no objection from any sane DM.

That said...

It is a bit boring and defeats the purpose of it (hence a subclass which simplifies everything).

If you do allow a 'lone rat' from the pack, then the easiest way to rule this would be to treat it as find-familiar where you can see through its senses etc, but if you die, you don't become your familiar (surprise surprise).

Likewise, swarms splitting into two parts is a fun subclass feature.

My favourite of course was that you could Wild-shape as a reaction (to get the resistance and also because the rule of cool) rather than bonus action like the Moon Druid.

[Segev]

This is unrelated, oddly enough, from the reason I started the thread, but I'm playing an Aberrant Mind sorcerer in a game right now whose power comes from the fact that he is followed everywhere by a swarm of cranium rats. It's an open question whether the mechanically-human character is just a humanoid puppet for the hive mind, or the hive mind is subservient to his strong will (that is nevertheless driven slightly mad). The character genuinely isn't sure if he is the rat swarm with the human's memories, or the human controlling the rat swarm.

I have represented his swarm with the Retainers background. The three commoners are only capable of things commoners could do, but represent, mechanically, the rat swarm (which can subdivide into up to three smaller swarms). He also has several of his spells refluffed as the rats doing things. Mold earth is the rats digging supernaturally fast. Sword burst is the swarm surging up and biting those adjacent to him. That kind of thing.

Now, I'm not trying, with him, to get more swarms or anything; I actually wrote this thinking about a druid (he's level 8 and Circle of the Land: Underdark, so a subclass about swarms won't help him) I'm playing and how cool it would be to dissolve into a swarm of moths or spiders as more than a visual on misty step.

[Goobahfish]

This is unrelated, oddly enough, from the reason I started the thread, but I'm playing an Aberrant Mind sorcerer in a game right now whose power comes from the fact that he is followed everywhere by a swarm of cranium rats. It's an open question whether the mechanically-human character is just a humanoid puppet for the hive mind, or the hive mind is subservient to his strong will (that is nevertheless driven slightly mad). The character genuinely isn't sure if he is the rat swarm with the human's memories, or the human controlling the rat swarm.

I have represented his swarm with the Retainers background. The three commoners are only capable of things commoners could do, but represent, mechanically, the rat swarm (which can subdivide into up to three smaller swarms). He also has several of his spells refluffed as the rats doing things. Mold earth is the rats digging supernaturally fast. Sword burst is the swarm surging up and biting those adjacent to him. That kind of thing.

Now, I'm not trying, with him, to get more swarms or anything; I actually wrote this thinking about a druid (he's level 8 and Circle of the Land: Underdark, so a subclass about swarms won't help him) I'm playing and how cool it would be to dissolve into a swarm of moths or spiders as more than a visual on misty step.

That is hilarious.

[KorvinStarmast]

Wild shape, polymorph, conjure animals... whenever a tool lists what they can turn things into or call up, swarms are excluded. {snip}

So, why the limit? If the limit is not RAW, why is it assumed?
TBH, I suspect that not turning into swarms is a "munchkin prevention measure" in intent, or as noted above, not worth the bother.

Beyond that, if you once again read the description from the MM that Amnestic provided,
the swarm has an element of "it already took some kind of magic to make this swarm form and behave the way it does" so it isn't a creature per se.
This means that if you are trying to justify polymorphing into a swarm you are getting to cast a spell that creates a different magical effect than what's on the tin for Polymorph. (Wish does that, but it's ninth level, not fourth).
It isn't the little creatures that make a swarm deadly (see swarm of quippers) it is a kind of magic (not available to PCs generally) that creates the swarm, and it is assumed to be malevolent from a lore perspective.

[Segev]

TBH, I suspect that not turning into swarms is a "munchkin prevention measure" in intent, or as noted above, not worth the bother.

Beyond that, if you once again read the description from the MM that Amnestic provided,
the swarm has an element of "it already took some kind of magic to make this swarm form and behave the way it does" so it isn't a creature per se.
This means that if you are trying to justify polymorphing into a swarm you are getting to cast a spell that creates a different magical effect than what's on the tin for Polymorph. (Wish does that, but it's ninth level, not fourth).
It isn't the little creatures that make a swarm deadly (see swarm of quippers) it is a kind of magic (not available to PCs generally) that creates the swarm, and it is assumed to be malevolent from a lore perspective.

Hm.

One thing I've pondered is the possibility of using animal friendship and speak with animals to gather and train critters and FORM a swarm that's loyal to the caster. The precise numbers needed are unknown but large, though whether you'd need to individually charm each one or could get away with charming a handful or three and then using Animal Handling to train others to follow their lead is another matter. Basically, though, this boils down to, "Can you come up with enough of an excuse to talk a DM into it?" so it's not really mechanical other than looking at what tools are available to build the narrative justification.

If polymorph and conjure animals don't include swarms and it would take different magic to make them, what level spell would conjure swarm be, using the same CR-and-number guidelines, but number of swarms called rather than number of individual creatures? Or, in the case of dissolve into swarm - a hypothetical polymorph-equivalent that lets you turn into a swarm instead of one creature - using the same CR guidelines for what kinds of swarms are available (maybe still restricted to beast swarms, though most if not all swarms printed ARE beast swarms). ...that got away from me a bit. Would such spells be the same level as their non-swarm counterparts? A level higher? Too powerful at any level?

[KorvinStarmast]

One thing I've pondered is the possibility of using animal friendship and speak with animals to gather and train critters and FORM a swarm that's loyal to the caster.

Spells do what they say that they do. I think you may need to home brew a spell, TBH.

If polymorph and conjure animals don't include swarms and it would take different magic to make them, what level spell would conjure swarm be, using the same CR-and-number guidelines, but number of swarms called rather than number of individual creatures? While I am not interested in doing that work for you (don't have the time these days) I recommend that you post your draft of your proposed Home Brew Spell in the Homebrew forum and let the community help you figure it out. You may arrive at something useful / worthwhile.

FWIW: as I read the MM, the magic behind a swarm is "create swarm" not "conjure swarm" ... but that may be splitting hairs a bit.

[Unoriginal]

Being a Swarm gives you most of the bemefits from Gaseous Form with next-to-none of the drawbacks.

I suppose that can give a good indicator of how powerful such a spell can be.

[verbatim]

Would it break anything for Conjure Animals to call forth Swarms of the correct CR?

A Druid dropping Four Rot Grubs on an encounter is probably the most notable thing this would enable.

[Joe the Rat]

On the "fingernail rat" issue, thinking about the swarm as the combination of creature and behavior is the core for curtailing multibody weirdness. You are not 1,000 bees, you are a swarm behavior that has drawn 1,000 bees. The you in this case is the spirit of the swarm (a Schwarmgeist if you will). Hell, the swarm doesn't necessarily have to be a transformation of your body - this could be a conjuration of beings, or a compulsory summons from the environment, driven by your now-disembodied will. Basically, you become an ever-vaguely-defined spirit (it exists, but does not interact with anything except through the rules of what called the spirit in the first place) that calls or summons the creature swarm. Individual creatures don't matter, because you are not a creature, you are the groupthink will of the whole.


Hmm... this reminds me, I need to make elemental motes and mote swarms.

[Unoriginal]

On the "fingernail rat" issue, thinking about the swarm as the combination of creature and behavior is the core for curtailing multibody weirdness. You are not 1,000 bees, you are a swarm behavior that has drawn 1,000 bees. The you in this case is the spirit of the swarm (a Schwarmgeist if you will). Hell, the swarm doesn't necessarily have to be a transformation of your body - this could be a conjuration of beings, or a compulsory summons from the environment, driven by your now-disembodied will. Basically, you become an ever-vaguely-defined spirit (it exists, but does not interact with anything except through the rules of what called the spirit in the first place) that calls or summons the creature swarm. Individual creatures don't matter, because you are not a creature, you are the groupthink will of the whole.

Which makes that powerset considerably out of the "Beast and Beast accessories" field.

[Segev]

Reading the rot grub swarm, what on earth were the designers thinking? It's a death sentence if you can't manage to do fire damage within 1 round. Any surprise, any reason at all you can't apply fire...and that's a dead PC, no matter his level. That's ludicrous.

The "hazard" that is the single rot grub would've been a far better model. Increase the constitution save DC to end the poison effect by 1 for every rot grub beyond the first, but allow a new save every time he takes fire damage. It's still way, way too much damage for CR 1/2, but at least that's manageable at a higher CR. I'd probably call it CR 2 or 3, considering its average damage on a hit is approximately 10, based on how 5e guestimates ongoing damage.

[Theodoxus]

This is unrelated, oddly enough, from the reason I started the thread, but I'm playing an Aberrant Mind sorcerer in a game right now whose power comes from the fact that he is followed everywhere by a swarm of cranium rats. It's an open question whether the mechanically-human character is just a humanoid puppet for the hive mind, or the hive mind is subservient to his strong will (that is nevertheless driven slightly mad). The character genuinely isn't sure if he is the rat swarm with the human's memories, or the human controlling the rat swarm.

I have represented his swarm with the Retainers background. The three commoners are only capable of things commoners could do, but represent, mechanically, the rat swarm (which can subdivide into up to three smaller swarms). He also has several of his spells refluffed as the rats doing things. Mold earth is the rats digging supernaturally fast. Sword burst is the swarm surging up and biting those adjacent to him. That kind of thing.

Now, I'm not trying, with him, to get more swarms or anything; I actually wrote this thinking about a druid (he's level 8 and Circle of the Land: Underdark, so a subclass about swarms won't help him) I'm playing and how cool it would be to dissolve into a swarm of moths or spiders as more than a visual on misty step.

I was thinking this morning about how vampires do it, and this basically boosts that thought. I'm away from book, so can't check, and I've never run a vampire in 5E, so maybe they don't even have the swarm of bats/rats ability... but if they do, whatever general rules there are for a vampire, I'd use for a Druid.

[Unoriginal]

Reading the rot grub swarm, what on earth were the designers thinking? It's a death sentence if you can't manage to do fire damage within 1 round. Any surprise, any reason at all you can't apply fire...and that's a dead PC, no matter his level. That's ludicrous.

I mean, things that remove diseases also work.

[JackPhoenix]

On the "fingernail rat" issue, thinking about the swarm as the combination of creature and behavior is the core for curtailing multibody weirdness. You are not 1,000 bees, you are a swarm behavior that has drawn 1,000 bees. The you in this case is the spirit of the swarm (a Schwarmgeist if you will). Hell, the swarm doesn't necessarily have to be a transformation of your body - this could be a conjuration of beings, or a compulsory summons from the environment, driven by your now-disembodied will. Basically, you become an ever-vaguely-defined spirit (it exists, but does not interact with anything except through the rules of what called the spirit in the first place) that calls or summons the creature swarm. Individual creatures don't matter, because you are not a creature, you are the groupthink will of the whole.

Granny Weatherwax would've approved.

[Segev]

I mean, things that remove diseases also work.

Which will generally be a very limited resource if available at all, especially at low level. Remember, this is a CR 1/2 creature!

[verbatim]

Not sure if they were there originally or added by the DM but the first time I encountered Rot Grubs was in a republished AD&D adventure in Saltmarsh for 5e. I actually tried the burning thing after the DM started making a big deal about how it was urgent, his irl brother did not...

I can't find the original but I wonder if the way it's written is meant to be true to the original 2e statblock, given how different it is from most 5e monsters.