There is often some confusion about stealth and invisibility in 5th edition Dungeons & Dragons. Some of the confusion isn’t actually all that confusing once you dig into it, but it turns out that some of the confusion is deliberate: we’ll get to that later. I will try to describe the issues and their official resolutions (or the less official resolutions) as we go through an example which happens to be current for me. In one of the games in which I am playing, I am planning a stealth mission. I am trying to ascertain in advance how to best use our advantages to ensure that we remain unseen throughout the entire process. There are a number of elements which come into play here. First, we start with the obvious: the individual Dexterity (Stealth) check. This is pretty simple: roll 1d20 and add your Dexterity (Stealth) modifier.
Now, if you’re like me, you know that a stealth roll for a 7th level druid doesn’t give a great probability of going undetected, even if you have a really good Dexterity (Stealth) modifier (spoiler: I don’t- it’s OK, but nothing to write home about). Since that alone doesn’t really guarantee anything like success, we really need to bump up our chances a bit if it’s important that we not be caught. Some character classes are born to stealth, but even ones like mine, which aren’t fantastic at it, can manage to stealth around with a little help from their friends.
What if we make ourselves invisible? Sounds like a winner, right? But what, exactly, does invisibility do? In what way is invisibility affecting our likelihood of being found? Well, according to the Player’s Handbook (p.291), invisibility is classed as a condition. It states that “An invisible creature is impossible to see without the aid of magic or a special sense. For the purpose of hiding, the creature is heavily obscured. The creature’s location can be detected by any noise it makes or any tracks it leaves.” It also discusses attack rolls, but we’ll ignore that for now since we are trying to sneak around to keep it from getting that far.
OK, so now we’re getting somewhere. When we now look up what “heavily obscured” does, we get the following description from the Player’s Handbook (p.183): “A creature effectively suffers from the blinded condition when trying to see something in that area.” OK, not as helpful as I was hoping for, but let’s follow this further down the rabbit hole. Looking up “blinded” brings us to page 290 of the Player’s Handbook, back in the Conditions section where we started this trip, just the page before the section on invisibility. Under the blinded condition, it states that, “A blinded creature can’t see and automatically fails any ability check that requires sight.” That took us the long way around, but basically what that tells us is that if the Wisdom (Perception) checks from creatures in the area involve sight, the sight part automatically fails. On the other hand, if the creatures primarily (or especially if they entirely) use senses other than sight, then invisibility has little/no effect.
What should we do now to figure out how invisibility affects rolls? We know what to do when a creature is invisible and sight is the only relevant sense for the potential observer (it’s an automatic fail). We know what to do when a creature is invisible and the potential observer has senses which allow it to see either magically or through some sense other than vision, like blindsight or truesight (the invisibility is ignored). What do we do when a creature is invisible and the potential observer has a suite of senses, vision being only one in that toolkit? First, it is obvious that if the invisible creature doesn’t actively stealth/hide, their presence will be discovered. You can hear people walking around unless it’s very noisy in your vicinity, moving often produces visible motion of nearby objects or footprints, and creatures with a decent sense of smell can often spot other creatures’ smells easily enough. I can’t find that there is anything official explicitly written about it. We can however make some assumptions based on some other rules. “Keen Hearing” and “Keen Smell” give advantages to Wisdom (Perception) checks which rely on sense of hearing or smell. In addition, going back to page 183 in the Player’s Handbook and looking at “lightly obscured”, we see that it gives disadvantage to Wisdom (Perception) checks (or subtracts 5 from their passive score) which rely on sight. It appears that advantage and disadvantage to the creature making the Wisdom (Perception) check are the options at play here. Invisibility would obviously NOT be significantly adversely affecting creatures with either keen smell or keen hearing. When encountering those creatures you would still need to make a good stealth roll to slip past them, since they will still be potentially rolling at advantage. Unless you decide that being unable to use their vision should cause them to roll at disadvantage, while using the other sense at advantage cancels out and requires a straight roll. This is a dungeon master’s discretion situation though, as it’s not found in the official rules. The invisible creature’s Dexterity (Stealth) roll would have to show that they were being very quiet, as well as taking into account things like not going upwind of the other creature or masking their scent. It is still possible in this situation for the invisible character to either succeed or fail, depending upon the rolls of the two opposing creatures.
This also still leaves the question of what to do when dealing with normal creatures (ones which use vision but without especially keen smell or keen hearing). Nobody official seems to give a definitive answer to this question. The consensus among players seems to be that disadvantage to Wisdom (Perception) checks (or -5 to passive) seems to make the most sense for creatures with decent, but not great, hearing and/or smell, to make up for the loss of a (if not the) major sense used for locating other creatures. Humans, for example, have pretty good hearing and pretty terrible senses of smell (we can often smell strong odours, but can have difficulty quickly localising them). We would definitely be at a disadvantage when trying to pin down the precise location of something invisible. In fact, a -5 penalty seems pretty generous for humans, when you think about it that way. When a mouse has died in your kitchen and you can smell it, think about how long it takes you to figure out where it is, bearing in mind that each 6 second interval is one round. And I like to think that most adventurers have considerably less of a smell than a dead mouse. Well, apart from barbarians, maybe. Regardless of all of that, one thing that is clear from the rules is that actual attacks against an invisible creature have disadvantage regardless of how good your ears or nose are, unless other means of seeing are used. Of course, if the attacking creature has absolutely no idea where the invisible creature is located, they may have no chance at all to hit. If they are swinging completely wildly, the invisible creature may not even be in the 5 foot space where they are swinging, in which case they will definitely not hit.
Why don’t D&D’s designers love us enough to explain what happens?
So why have the designers of Dungeons and Dragons 5E not chimed in on this confusing aspect of the game? Well, it turns out that they have. Jeremy Crawford, principles rules designer and lead designer of the Player’s Handbook for D&D 5E is recorded in a podcast speaking about it, and I would recommend listening to it. He describes the process by which they deliberately chose to make some of the rules for this less cut and dry, to allow the dungeon master to adjudicate based on the current situation. I respect that. Listen to it to better understand their rationale. It works for me.
So after all that, what do we definitely know about invisibility then?
Although there is some confusion about what invisibility can do, there are a few things which are clear about invisibility. Invisibility gives you the opportunity to hide in plain sight. Creatures which use other senses to “see”, like blindsight or truesight, are unaffected by invisibility. Also, invisible creatures attack with advantage- that part is crystal clear. Attacks against invisible creatures are at disadvantage unless they can be “seen” by magical means or through blindsight or truesight. In addition, opportunity attacks against the invisible creature can’t happen at all without magical means or ways to see without using normal vision (Player’s Handbook p.195; opportunity attacks are only against creatures you can see). Finally, many spells require you to be able to see your target, so those spells cannot target invisible creatures (and some friendly spells also sometimes require the spellcaster to see their targets OR the creatures not to be targeted by unpleasant effects) which also changes the dynamic substantially for invisible creatures.
Getting better at not being found
OK, so now to get back to our stealth mission. We are stealthing, and we’re invisible (which allows us to stealth in the open, and depending upon the DM may or may not include some sort of disadvantage to potential observers). What else can we do to make ourselves less likely to be perceived? One of my favourite ways to avoid being spotted is the spell Pass Without Trace. For an hour, it allows you and anyone within 30 feet to add a +10 bonus to your Dexterity (Stealth) score, and removes any tracks or other traces of your passage so that you cannot be tracked by non-magical means. Now we’re really talking! My character’s stealth bonus is +4 normally, so with Pass Without Trace it will be +14. This means that the lowest my Dexterity (Stealth) can be is 15 if I roll a natural 1. Adding on the invisibility, which will make it harder for potential observers to spot me, means that I am now unlikely to be spotted.
Getting even better at not being found
So far, this is very good, but can we make it better? Well, there’s another spell called Enhance Ability, which allows you to enhance a certain aspect of one’s abilities. In this particular case, the Cat’s Grace aspect of the spell gives the target advantage on Dexterity checks. This means that not only will I get advantage added to my Dexterity (Stealth) checks (with +14 added), after some flavour of disadvantage is added to potential observers’ Wisdom (Perception) checks, but advantage will also be added upon arrival at my destination for a Dexterity (Sleight of Hand) check. Since these three spells all interact with different aspects of my Dexterity (Stealth) check or the opponent’s Wisdom (Perception) check, they do not fall under the rule where when overlapping spells interact only the highest one functions. Instead, the synergy of these spells produces an amazing heist character, where an hour previously a simple 7th level druid with proficiency in Dexterity (Stealth) once stood. My character will now have a 15-34 Dexterity (Stealth) score, trending towards the higher end of that range thanks to my advantage, while my opponents will have a lower than usual Wisdom (Perception) score to find me. If my lowly, unsneaky druid can do this well, imagine if a rogue were operating under the same set of circumstances! The role that invisibility plays is the only inconclusive aspect of this situation, as your DM will need to decide for themselves how they choose to rule it, but regardless of what they choose, it will certainly help make your situation better.
Hopefully this will clarify some of the confusing elements of how stealth and invisibility interact, or if you’re a dungeon master, will give you an idea of what you will need to think about for when the situation arises. It’s fairly complicated at first, but once you get into it, it’s not really so bad in the end.