Is allowing swarm-shaping unbalanced?

[Magicspook]

So for an upcoming campaign, I have a player who is planning on playing a barbarian, then multiclassing to moon druid after 5 levels. This player has expressed the desire to wild shape into swarms. Now I have always thought this was a very cool idea, which makes me reluctant to say no, but I have no idea if this will unbalance the game somehow. What are your thoughts on this?

FYI his barb subclass is totem and I do not think he has any plans on going beyond moon druid 2.

[AdAstra]

I mean the damage-resistances are already provided by rage (they wouldn't stack). I might be worried about the condition immunities, but the highest-level swarm in the Monster Manual iirc is the CR 2 Swarm of Poisonous Snakes. As cool as it is it kinda runs into the issue of how one can shapeshift into a large number of individual creatures. Why wouldn't the druid be able to wildshape into say, 2 wolves? What makes rats different from wolves that allows you to turn into multiple of one and not the other?

[Damon_Tor]

As cool as it is it kinda runs into the issue of how one can shapeshift into a large number of individual creatures.

I'm gonna say "magic".


Why wouldn't the druid be able to wildshape into say, 2 wolves?

Sounds awesome.

[Crgaston]

So for an upcoming campaign, I have a player who is planning on playing a barbarian, then multiclassing to moon druid after 5 levels. This player has expressed the desire to wild shape into swarms. Now I have always thought this was a very cool idea, which makes me reluctant to say no, but I have no idea if this will unbalance the game somehow. What are your thoughts on this?

FYI his barb subclass is totem and I do not think he has any plans on going beyond moon druid 2.

I love this idea as well and am disappointed there isn't an official mechanic for swarmshifting.

I think so long as you're mindful of the other restrictions (swim and fly speed) it will be fine. Maybe some hydrophobic poisonous snakes?

Swarms can't regain HP or get temporary HP so you'll have to decide how this interacts with the Combat Wild Shape healing-for-spellslots feature. This might be a worthwhile tradeoff for the snakes' swim speed.

Because turning into a cloud of wasps is cooler than turning into a carpet of spiders, you could allow a swarm of FSI's (flying, stinging insects) if you limited the flight to no higher than 10' (and make it unable to cross rifts greater than the Barbarian's jump distance) without breaking the spirit of the no-flight rule.

I also like the idea of an anthropomorphic swarm, where the insects are all climbing on each other in a vaguely humanoid shape.

[Magicspook]

Thank you everyone for your input! Since it seems you agree that it is not too overpowered, at least at 7th level, I think I'm going to give my player an opportunity to do swarm-shaping. His race is Fomorian (which is a type of goatmen which used to have a great empire back in the day), and I am considering granting him this ability as a reward for choosing a side within Fomorian politics (without going too much into detail, the two factions are the natury treehugging faction and the anti-human lets-rebuild-our-empire faction). Heck, I might consider plantshaping as a reward for joining the other side.

[Knaight]

I like the idea, though you might have to write up some homebrew swarms to make this work. I figure if it's good enough to be an established trope for vampires (bat swarm, rat swarm) it's good enough to work for a shapeshifting druid.

[Segev]

The swarms in 5e are nowhere near as potent as the swarm subtype in 3e. They're just monsters. Go to town, I say.

[Urukubarr]

reminds me of turning into rats in dishonored, and now I have a druid idea.

[Dudu]

Flavorwise, it can be pretty cool.

The barbarian part looks exotic, though. When I think swarm shapeshifting, what comes to my mind is a powerful vampire turning into a swarm of bats, or elusive spy turning into a swarm of spiders. Cool stuff.
And I don't think it's broken. Atypical, not broken.

[sithlordnergal]

So, thanks to the Barbarian there isn't really much to worry about with resistances. As far as can remember, there's really only one swarm you have to worry about, and that's the Rot Grub Swarm.

They have a +0 to hit, but if they do hit and manage to infest a target, that target will die no matter what if they don't have a way to cure disease. Its an unavoidable 1d6 per round.

[Misterwhisper]

While the idea is interesting I am not sure how it would work for the barbarian.

Ex. You don't really have a solid form, and have resistance already so what is rage going to do?

I just see them as being very different from each other.

The barbarian will more than likely be raging and swinging a strength based weapon at people but then it shifts into a swarm of spiders/ant/bees whatever and just kind of floats around people?

I would put a limit on it of only creatures with an INT of 1 like insects, arachnids and the like, never like rats, or bigger.

I could see this making a rather cool Druid subclass though.