Are Warforged affected by a troglodyte's Stench or other poison-based effects?

Question

In the Warforged's description, it states that they don't need to breathe. So one of my players told me he would shut down his smell sensors or something like that so he won't be affected by something like the Stench effect of a troglodyte.

Some poison-based spells explicitly state that they still work when someone holds their breath, like Cloudkill. The Stench effect does not mention the case of holding one's breath.

Can a warforged make himself immune to things like Stench as a trade-off of not smelling anything?

Answer 1

There's two stacked issues in this question.

1. Can a warforged smell things at all?

2. If they can, does being able to smell but not needing to breathe protect it from foul smells?

Starting with the second question, the game doesn't say warforged can't smell, and we generally assume that you can do normal human things that are not explicitly excluded.

However, it does say they don't need to breathe, and there is precedent for not needing to breathe granting protection from bad smells. The spell stinking cloud explicitly says creatures that don't need to breathe automatically save. It doesn't say creatures that can't smell are immune, only ones that don't breathe, which suggests that those things go together.

Similar language is not present in other situations involving bad smells, though; for example, the troglodyte's stench and the ghast's stench have no such clause, which means that non-breathing creatures must still save against the poison effect.

But that said, this is a weird sort of corner case, because Warforged represent the only non-breathing PC race, and the only (semi-)construct race. As a late addition to the game, earlier resources may not have even thought about the possibility of PCs that don't inhale gasses, so such oversights could reasonably be chalked up to "warforged are weird" and be house-ruled accordingly.

In his appearances on the Dragon+ YouTube videos, Jeremy Crawford has mentioned a couple of times that spells and abilities intentionally don't call out all the exceptions and corner cases, in the interest of making their basic effects clear and concise rather than bogging them down in an infinite tangle of minutia. The DM is expected to make rulings on those cases when they're necessary.

So, ultimately, there's no specific rule that says Warforged are immune to bad smells or can close off whatever chemical detectors they may or may not possess to simulate a sense of smell; but there's a precedent for a DM to rule that bad smells don't bother Warforged and/or that they don't even have a sense of smell, and the designers intend DMs to do that when it seems appropriate in their own game.

And of course, the Wayfinder's Guide lives somewhere in the limbo between playtest content and an official release. The devs have already stated that the 5e Eberron book coming out in November has updates to the Warforged, among many other things previously released in the Wayfinder's Guide, and may address questions like this more clearly -- but don't hold your breath. (geddit?)

Answer 2

Yes, they are affected by Cloudkill, other effects may vary

Cloudkill specifies at the end:

Creatures are affected even if they hold their breath or don't need to breathe.

This specifically tells us that it doesn't matter that the Warforged doesn't need to breathe, they are still affected.

Other effects

For each effect you'll need to look at the wording including. If it includes language like the above, then it gives you some information. If doesn't include language like "creatures that can see" or "creatures that can breathe" as part of it's targeting, then not being able to breathe shouldn't be a concern.

However, it is also up to a DM as to whether or not they feel an undefined effect requires it. They may rule as such, but with magic and mundane, there is more than one way for an effect to cause an issue (either through other orifices or even skin contact.)

Answer 3

Although they are constructs, they aren't capable of picking and choosing which of the senses are active for the purposes of avoiding effects, and I can see this being a slippery slope if you allow it. "Shutting down smell sensors" is not something a Warforged is explicitly capable of. This is absent from Unearthed Arcana, where they're introduced, as well as every other source book.

Would you allow them to turn off their visual sensors if an enemy casts Hypnotic Pattern? Or shut off their hearing sensors to negate a Shatter spell? The answer to both is probably no. A racial passive that gives immunity to effects would not be balanced.

Answer 4

Historically, warforged weren’t able to smell at all without a special attachment. The description for the 3.5e tracker mask warforged component, which gave warforged the special scent ability (similar to wolves etc.), said

many warforged covet this item because it gives them the ability to smell all scents, not merely those of a creature being tracked

^{(Races of Eberron pg. 176)}

However, it’s worth remembering that the 3.5e warforged were also just flat-out immune to all poisons in the first place (“—Immunity to poison,” Eberron Campaign Setting pg. 23). Cloudkill didn’t work on them even if they had tracker’s mask. Troglodyte stench likewise specified that “creatures with immunity to poison are unaffected.”

Ultimately, stenches and inhaled poisons are not usually that important to my games, and I would have no problem with the warforged being immune to them, since while 5e warforged are not immune to poisons as they were in 3.5e, they are not required to breathe. If you are using a premade adventure, you might see how significant they are in your game. If not, just keep it in mind. Personally, I would allow the warforged to avoid a troglodyte stench—after all, warforged don’t have to breathe, so they can just not. Cloudkill, on the other hand, damages creatures without needing to be inhaled, and since 5e warforged do not have immunity to poison, I would have that affect them.