What happens if a Player Misty Escapes into an Invisible Creature

Question

The Archfey warlock patron grants the Misty Escape feature at level 6 (PHB p. 109). Part of the description of the feature states:

When you take damage, you can use your reaction to turn invisible and teleport up to 60 feet to an unoccupied space you can see.

Now, if a space was occupied by a creature that was already invisible, and if the character had no prior knowledge of its existence, it would appear unoccupied.

Say a player picks a space on the battlefield, one that the GM knows is occupied by an invisible creature.

Does the character "appear" in the invisible creature, suffering and inflicting some effect, or do they just "bounce off" into the next available space?

Answer 1

Resolve the edge case with an impartial ruling: random location via die roll.

Since the rules don't explicitly define what happens in a case like this, and since the class ability moves the PC into a place that is based on PC knowledge, letting go of the gridbound mind set is a simple way to resolve this unexpected encounter. This link is to a similarly inexact situation regarding players being spit out of a gelatinous cube.

or do they just "bounce off" into the next available space?

That's a fair and simple way to resolve this: the PC bounces of the invisible obstacle. The PC still gets to escape the current problem, but due to the ever present problem of dealing with "the unknown" something unexpected happens when taking this action.

• This is a common pattern in play at the table: for example when dealing with unseen traps or invisible barriers. The PC moves with confidence from "here" to "there" and something unexpected happens along the way

Die rolls are used to resolve uncertain results: use the available tool

The basic framework of "How to Play" is retained. (PHB p. 6)

1. DM describes the situation
2. Player describes the desired action
3. DM narrates results
   (Roll dice when the outcome is uncertain).

Roll a 1d8 (if using a square grid) or a 1d6 (if using a hex based map) and assign the number 1 to relative north (top of the map). Move clockwise around the grid or hex pattern to determine where the warlock unexpectedly ends up.

Example of a bump:

• On a roll of 4 on a d6, the warlock ends up directly below the hex she was escaping to. (relative "south" to the top of the map)

• On a roll of 3 on a d8, she ends up directly to the right of that space. (relative "east) to the top of the map)

  What does this ruling do for you(DM) and for the player?

• It keeps play moving

• It removes any hint of DM influence on the final destination

• It preserves the location of the invisible creature

• It provides a surprise/unexpected outcome due to incomplete player knowledge -- which is OK since the players are dealing with the unknown a lot during their adventures

  I've used this quick and easy tool for unexpected things like this (most commonly for our old "shooting into melee and you missed, what did you hit?" scenario in a couple of older editions) since around the time I began DM'ing.

In my experience, this way of making an ad hoc ruling based on an unexpected situation is both quick and fair. It has been with the game as long as it's been played. I learned it from DM's before me.

The dice are a tool. In this case, what the dice do is keep it fair and random. This also frees the DM from having to explain why the PC ended up on a given square. Fate/chance took over when the PC bumped into an unseen obstacle at its destination.

Answer 2

The short answer is to ask your GM.

There are no official rules regarding what happens if a target is invalid unbeknownst to the character. According to Jeremy Crawford, lead designer, in a podcast, this is because invalid targets didn't come up in the playtest.

However...

Xanthar's Guide to Everything has an optional rule for similar edge cases but it only addresses spells directly (Misty Escape is a class feature not a spell):

If you cast a spell on someone or something that can’t be affected by the spell, nothing happens to that target, but if you used a spell slot to cast the spell, the slot is still expended.

You could apply similar logic to the class feature, in which case your feature is expended and you don't teleport (but you will turn invisible since the target of that effect is not invalid).

Answer 3

It's up to your DM

According to Jeremy Crawford, there are no rules for when a target is invalid. This paraphrased transcript of this podcast indicates that

The 'design intent' is that nothing would happen, meaning the action is wasted, but a spell slot would not be spent. Ultimately, the rules are silent, so it is up to the DM.

He also has this to say about temporary invalid targets. (Source)

There's no rule governing what happens when a valid spell target temporarily becomes an invalid target. A good rule of thumb is that the spell is suppressed while the target is invalid. #DnD

So according to designer intent, you can't misty step into that area. Your character would be aware of that. It's up to your DM if they let you misty step anyway, either near the point, into the point, or a point of your choosing.

Answer 4

As has been mentioned in other comments, the developers have confirmed that there aren't any concrete rules for this, and whoever is DMing it will have to make a judgment call. However, here are my thoughts. Since it's a special ability (not a spell), the entirety of the rules governing it are covered in its description.

Starting at 6th level, you can vanish in a puff of mist in response to harm. When you take damage, you can use your reaction to turn invisible and teleport up to 60 feet to an unoccupied space you can see. You remain invisible until the start of your next turn or until you attack or cast a spell.

So, when you take damage, you have the choice to use your reaction to turn into mist. If you do, then congratulations! You're an ephemeral, invisible mist. (To answer your recent question: I believe that turning into mist acts as an effect that targets Self.)

Now that you're out of immediate danger, your misty-self must relocate to a new spot. When selecting the spot, three qualifications must be met. First, you have to be able to see it. Second, it has to be within 60 feet. Finally, it has to be unoccupied. Since we know that the rules don't adequately cover the edge case you're asking about (where the space in question is actually occupied, but you're unaware of it), then the DM has to make a ruling. There are basically three options:

1. The DM decides to punish you for using your class ability, and declares that the whole thing is negated. You waste your reaction and your class ability, you're still visible, and you stay in the danger zone. (I dislike this option.)
2. Same as the above, except the DM also decides to treat the attempt like dimension door, causing you to suffer 4d6 Force damage as you unknowingly try to move into an occupied space. (I hate this option).
3. The DM decides to apply some creative reasoning, and refers to the descriptive text of the ability. Now the real job of a DM begins: taking the unique situation at the table and thinking outside the box.

While the rules state that this movement is treated as a "teleport," the descriptive text makes it clear that the narrative intent is that your mist form is moving through the battlefield without having to pay attention to things like difficult terrain, opportunity attacks, or partial obstructions (like prison bars or a wide chasm). However, unlike a "true teleport," you're not actually vanishing-and-reappearing. Instead, your mist form is quickly moving across the battlefield.

With that in mind, if you turn into mist and move toward the intended location, it makes sense that you would immediately be aware of a space that you cannot physically fill. You may not know why (other than the DM telling you that you can't), but that's okay—you're still in mist form!

Now that you know you can't fill that spot (because the DM told you/your mist-self wouldn't fit there), it's time to adjust your landing point accordingly. As long as your final landing spot is within 60 feet of your origin point, and visible from that point, then your mist eventually coalesces and waits until the start of your next turn.

If I'm the DM at the table, that's my ruling. The player gets to use their class ability in the exact kind of emergency situation it's meant for, and I'm spared feeling like a jerk for punishing the player for something that I was hiding from them.