False appearance and hiding mid combat

Question

As per the title, I'm having a hard time to understand how these two abilities interact, more specifically in a case of a homebrewed monster that can blind creatures that failed a save. It goes as follows:

• the monster uses its ability.
• the 2 PCs failed the save and were blinded.
• the monster used this opportunity to hide, as while motionless it's indistinguishable from the nearby terrain.

Now, at the time I ruled as I saw fit, but now I'm having trouble to actually understand how this should work in a more RAW view. On one side, the creature technically could just lay down and that would be it, as it'd become indistinguishable from the environment around it and effectively hidden. However, the monster is still not hidden, and so the players are still aware of its location and can hear if it moves to another place to become motionless, requiring it to succeed on a stealth check in order to successfully change its position before becoming motionless, which is the way I ruled.

With that said, rules as written with little to no added common sense, can a creature with false appearance simply conceal itself anywhere as long as its in an environment where its ability can work? Does it need to succeed at any stealth attempt to "hide" (and I use the word loosely here because false appearance is more about not being recognized rather than not being seen at all) from other creatures using its false appearance skill?

Answer 1

False appearance works more like a disguise then hiding

You didn't give the precise text of the monster's abilities, but based on your description, I infer that you have based the monster's "False Appearance" trait on the wording of one of the many official monster stat blocks with a trait of the same name. Let's take the Awakened Tree as an example. The tree has the following ability:

False Appearance. While the tree remains motionless, it is indistinguishable from a normal tree.

When an awakened tree remains motionless, it is not hiding. It remains plainly visible, so it cannot be hidden. Instead of obscuring the location of the awakened tree, this ability causes creatures who see the tree to wrongly recognize it as an ordinary tree, much like a disguise self spell might cause someone to wrongly believe that an arcane trickster rogue is a town guard. Although the False Appearance trait is actually better than a magical disguise, because unlike disguise self, False Appearance doesn't allow an observer to notice the ruse with a successful Investigation check.

So, let's analyze your scenario. The PCs were temporarily blinded, which means that the monster, regardless of its appearance, was unseen by those PCs and could attempt to hide. In this instance, "hiding" probably means remaining silent while moving to a new location and then holding still. If the monster succeeds on its stealth check, then while the PCs are still blind, they cannot hear where the monster has moved to and are now unaware of its exact location. When the PCs finally regain their sight, they can now see the monster, but they can't necessarily recognize it. Obviously, if they were fighting an awakened tree in the middle of a grassy field, there would be no doubt that the motionless normal-looking tree in front of them is in fact their enemy. On the other hand, if they were fighting in a quarry against a monster that has the false appearance of a rock, then unless they previously memorized the position and appearance of every rock in the area, they probably can't tell at a glance which one is the enemy and which ones are just rocks.

At this point, depending on the circumstances, you might allow a PC to make an intelligence check to recall the positions of all the nearby rocks so they can tell which one is out of place, or you might allow them to make a Survival check to locate the monster's tracks to lead them to the correct rock. Either way, it would probably require their action to do so, but if they succeed, then they could point out the enemy to the other PCs. Alternatively, perhaps one of the PCs has the Keen Mind feat, in which case they would simply remember where all the rocks were before they were blinded and easily identify the odd one out, in a rare instance of Keen Mind being directly combat-relevant. To summarize, if the PCs want to determine which rock is the enemy, they will have to use information other than the enemy's appearance, because the False Appearance trait specifies that the monster is "indistinguishable" from the type of object it is imitating, so simple visual inspection cannot reveal the disguise.

Again, we can draw an analogy to a disguise spell: suppose our arcane trickster rogue is trying to evade a guard. They could run around a corner, thus becoming unseen, and then cast disguise self and walk into a crowd. If you as a DM know how you would handle this kind of situation, you can apply similar rulings to the case of a monster trying to hide in plain sight using False Appearance.

Answer 2

False Appearance is not being hidden

Hidden means "both unseen and unheard" (p. 194 PHB). False Appearance does not make the monster unseen and unheard, it just makes it look like something else. Here is an example False Appearance entry from the Roper:

False Appearance. While the roper remains motionless, it is indistinguishable from a normal cave formation, such as a stalagmite.

You can see the stalagtite clearly. You just don't realize it is a roper. It is not hidden. If the monster wants to be hidden, it needs to follow the normal rules for hiding from the Basic Rules:

When you try to hide, make a Dexterity (Stealth) check. [...] You can’t hide from a creature that can see you clearly, and you give away your position if you make noise, [...]. An invisible creature can always try to hide. Signs of its passage might still be noticed, and it does have to stay quiet.

Hiding: If the characters are temporarily blinded, the monster is invisible to them and can attempt to hide in plain sight. It needs to succeed on a Dexterity (Stealth) check to do so. If it does, it can also use that check to move to another space quitely and without leaving tracks. Without a check or if it fails, the characters will hear if it moves to another space, and know where it moved to.

False Appareance: The monster also can use False Appearance to appear as whatever terrain feature it looks like, without needing to make any check. While the characters are a blind, they will not see the transformation.

Once the characters' blindness wears off, if there was nothing to hide behind, they will see the monster, and it will lose its hidden status because you cannot hide from a creature that can see you clearly. Their vision is not obsucred in any way, they can see the monster clearly, it just does appear to be something else, so that is true, wether the monster is using False Appearance or not.

Will the characters realize what is going on?

So if the monster did use False Appearance, the question then is if the characters (and players) will realize that the terrain feature they now see is the monster. This will is up to the players, you just describe what they see. They than decide if and where they want to attack.

• If the monster did not move, they heard no movement and now there is whatever it appears as in the space where the monster used to be.

• If the monster did move and failed or did not make a Stealth check, now there is whatever it appears as in the space where the characters heard the monster move to.

• If the monster did move and made its Stealth check, they heard no movement and now there is whatever it appears as somewhere in the vicinity. Depending on the rest of the environment, this may be obvious or hard to recognize: empty room without features - obvious. Room full of stalagmites with one extra stalagmite somehwere - hard, and likely worthy of an Intelligence check or similar to see if someone can pinpoint it, if they try to.

Special False Appearance

There is an extra wrinkle in that some kinds of False Appearance can make the monster appear as if there is no object there at all. Here is an example from the Trapper in Volo's Guide to Monsters:

False Appearance. While the trapper is attached to a ceiling, floor, or wall and remains motionless, it is almost indistinguishable from an ordinary section of ceiling, floor, or wall. A creature that can see it and succeeds on a DC 20 Intelligence (Investigation) or Intelligence (Nature) check can discern its presence.

In this case, if they know the space or not, they would not see anything unless they spend the effort to make an Intelligence check (which the DMs may rule to use their action for the turn). They might still attack the space where the monster was, or a space they heard to move it to, or a random space in the hopes of hitting it there. Or they might think it teleported away.

Answer 3

A very interesting question. Hiding has 2 criteria;

The DM decides when circumstances are appropriate for hiding. ... You can't hide from a creature that can see you clearly

Let's step through the situation;

1. The monster is seen and heard.
2. The monster uses its ability. The PCs failed the save and become blinded. The monster is now unseen.
3. The monster uses the Hide action, making a stealth check. The PCs do not detect the monster with their passive perception, so to them the monster is undetected (they can neither see it nor hear it).
4. The monster stands still, causing False Appearance to activate.
5. The blind effect wears off. The monster can now be "seen clearly", which means hiding must end.

Step 6 ends us in a situation the rules do not cover. Hiding has ended but the monster is undetected by the party. In this kind of situation the DM must make a ruling.

As a DM when faced with this situation I present it to the players and let them think of what to do. Here are some solutions that I might accept:

• "Do I see anything in the room that wasn't there before?" "Roll an intelligence"
• "Can I see any clues as to where the monster may have gone?" "Roll investigation"
• "Can I intently stare around and see if anything is breathing or moving slightly?" "Roll perception" (it will automatically fail but we don't need to tell the players that)

Answer 4

It seems to me that the rules for being "hidden" were written without considering the possibility of hiding in plain sight. For example, a creature can't be Hidden if it can be seen directly, whether it's recognized as a threat or not. But 5e rules are written to cover the common cases, and it's expected that human DMs will adjudicate special cases. This is one of those cases where simply applying written rules doesn't fully cover what would make sense. RAW does provide a framework we can use, of course.

"Hidden" as a game term has some mechanical consequences involving advantage on attacks, and other special case rules and class abilities.

A DM should decide on a case by case basis which of those things apply for a camouflaged creature, if it manages to make it non-obvious where it is. (Groody's answer goes into detail about making a Stealth check to move while the PCs are blinded, to move such that it won't be obvious which stalagmite is actually the roper, for example.)

I think the following rulings would be sensible for this corner case not covered by the rules:

• A camouflaged (hidden-in-plain-sight) creature can be attacked without disadvantage, so it doesn't gain that benefit of being Hidden from a creature attacking it. If a PC guesses right about which stalagmite to attack, nothing makes it any harder than usual to hit. In fact easier if the target doesn't move / dodge / defend itself (as if paralyzed).

  But the PCs do have to identify the correct "object" (or patch of room surface) to attack.

  An AoE effect like a Fireball would leave a stealth roper in the area with a choice to stay perfectly still (not even attempting the Dex save), or to use their dexterity at the cost of revealing themselves as a creature. (This is also not rules-as-written, not play-tested. I wouldn't apply it to creatures hidden normally; they can move, e.g. duck and cover, without automatically revealing themselves because they're behind cover.)

• A camouflaged creature may have advantage when attacking a target that didn't recognize it. Even mid-combat when the target knows there's a hidden Roper somewhere, the situation may or may not let the roper attack without the target seeing the threat coming until it's too late.

  This depends on range and whether a character might take their eye off it to look somewhere else; if a roper tentacle is right next to a PC, it could grab them by surprise. (Although to do bludgeoning damage, it probably needs to whip at them.) A stabby monster, or bite or pincer claw, could maybe be more effective like this.

  If a tentacle has to whip from across the room, a PC could see it start to move and defend as normal, especially when they know there's a hidden roper somewhere so they're on alert for what form of self defence to take.

  If a camouflaged creature can wait until their target turns their gaze away to look elsewhere, that could enable an attack with Advantage. That would depend on terrain. If there are other stalagmites in other directions, so the PC is mostly between the roper and some actual stalagmites, it's very reasonable that they can't keep them all in view at once.

So neither of these work exactly like being Hidden, but parts of the benefits can make sense.

Some of your choice of when to allow advantage will probably depend on how you rule about normal cases of attacking from hidden: if you pop out from behind a wall and fire a crossbow, were you actually hidden when you pulled the trigger if you popped right out into the line of sight of your target? Or run from hiding to stab someone.

You want to be consistent with how much time it takes for creatures to notice a new threat and make it not count as hidden anymore, in terms of whether a monster can start moving and get a sneak attack in, vs. PCs being able to attack from hiding by popping up from cover to take a shot. A quick snap of a whip-like tentacle could be similar to a crossbow wielder popping out from behind a wall to take a shot.