Are Unseen Servants usable in combat?

Question

Unseen Servants act as some sort of force that can perform simple tasks.

Is it possible to use them to aid in battle while doing so?

For example:

• Have several servants told to carry heavy large metal plates around some character. (Basically creating a barrier that would protect the character behind it.)

• Have a servant carry some alchemical substance and instruct it to drop it on the ground in the middle of the enemies.

I think there are many more abuses of "carry and drop" commands. But are they legal?

Answer 1

Unseen Servants are not meant or suited to be used in combat. Their combat utility, if your DM even allows it at all, is extremely limited.

An Unseen Servant can lift 100 pounds max, which is consistent with a strength of 5, and likewise cannot attack or take up space. As such, carrying a heavy metal plate doesn't present much of a deterrent. At best, it would give you maybe cover against ranged attacks. But possibly a bolt fired into the plate would cause the Unseen Servant to drop it anyway. Using multiple Unseen Servants doesn't overcome these limitations and is hugely impractical besides: they have the equivalent strength score of a puppy, so you'd need a lot of them holding on to that plate to make it even slightly difficult, and you need to instruct them all one by one to do it.

Any creature wishing to do so could easily push the Unseen Servant aside due to its low strength; it cannot stop anyone from simply moving past the plate to strike (as it takes up no space and cannot make opportunity attacks).

"Dropping" alchemical substance on the ground likewise isn't going to do much; an alchemical flask that would explode when casually dropped from waist-height would be very dangerous thing and much more force than that cannot be exerted by an Unseen Servant. There's a good chance the bottle wouldn't even break if dropped. You are supposed to smash them against something, which is why they usually involve making an attack (which the Unseen Servant cannot do).

Plus, the target of the potion could simply grab it as the Unseen Servant approaches with it and any kind of contested check would automatically be lost because the Servant cannot make attacks and has a really really low Strength score. Odds are good that you'll be eating your own alchemical potion if you try this.

So in addition to not being designed to do any of these things, care has been taken to make sure that even if you try, the Unseen Servant will be very ill-suited for these tasks anyways.

Answer 2

When you read the spell description, especially if you read it's evolution over several editions, it appears the intent was to word the spell in such a way as to prevent players from "weaponizing" the Unseen Servant. As always, the authors will only go so far in their spell description legalese, and rely on the GM to make the final determination.

So, when you say "Are they legal?", my first answer is: Yes, there are ways to use this spell in combat if you go only by what is written. However, you already knew that, as you've listed a couple of clever uses that would do just that and are not strictly prohibited by the text.

However, you're probably actually trying to ask one of 2 other questions:

1. I'm a player, and I want to weaponize this spell. Can I do that?

The answer here is: It depends on your GM. Ultimately, they'll decide what other restrictions are implied, intended, or necessary for their game, and that'll probably come down to a case by case series of attempts by you and responses by them. There's nothing wrong with this style of play. I've seen many tables that enjoy exactly this kind of maneuvering between players and GM. However, I can't really answer your question, other than perhaps giving you a litany of clever maneuvers for you to try and for your GM to adjudicate. Which I'm not going to do right now.

2. I'm a GM, and my players are trying to weaponize this spell. How can I rein that in?

Although the previous discussion still applies, I can provide a little support here. Generally, if a player's clever use of a spell is going to be restricted, they would like an in-game explanation of the mechanics that makes sense to them. As a GM in previous games, I've dealt with this issue by filling in a fact about this spell in my world that is not mentioned in the description. Timing. There's no indication of how quickly the unseen servant reacts to commands. To further the intent to prevent the use of this spell in combat, I added the fact that the servant's reaction time was not only poor, it was inconsistent, so getting it to stay positioned appropriately, or interact in a useful manner during the chaos of a battle is really just more trouble than it's worth.