What is the difference between "Unconscious" and "Asleep"?

Question

The Sleep spell explicitly causes targets to fall "unconscious" but includes many references to sleep, as well as the line:

"Undead and creatures immune to being charmed aren’t affected by this spell."

The Eyebite spell, on the other hand, states, as one of its options:

"Asleep. The target falls unconscious. It wakes up if it takes any damage or if another creature uses its action to shake the sleeper awake."

Although the name of this effect is "Asleep" there is no text in the Eyebite spell that indicates that creatures who do not sleep are immune, as in the Sleep spell. (I suspect that specific over general likely means that this Eyebite effect doesn't work on elves, but that's not really part of this question—I'm just providing context for the ambiguity here.)

The Dream spell states:

"If the target is asleep, the messenger appears in the target's dreams ..."

Once again, it includes a line indicating that creatures such as elves are immune.

The "Unconscious" condition of D&D 5e does not mention being asleep and there is no "Asleep" condition.

This question contains relevant discussion of whether elves can sleep, which I think mostly just muddies this question a bit more.

My question is whether there is a fundamental distinction anywhere in the rules between being asleep and being unconscious. Clearly elves can be unconscious without being "asleep," but can a human be unconscious without also being asleep? Given that the dream spell works on creatures who are "asleep" and not who are "unconscious" how can the DM tell if the creature I'm targeting is asleep or is unconscious-but-not-asleep? (Or: can I cast Dream on a human I just knocked unconscious and why or why not?)

Answer 1

Using Xanathar's Guide, you are unconscious while sleeping.

Xanathar's Guide actually has (optional) rules for sleeping:

While a creature sleeps, it is subjected to the unconscious condition.

It then goes on to give more detailed rules about sleeping that aren't material to this question. It should be noted that the rules printed in Xanathar's Guide are optional rules to be used at the DM's discretion.

Additionally, we should note that while sleeping means you are unconscious, being unconscious does not necessarily mean you are sleeping.

The Player's Handbook does not define sleep.

The Player's Handbook has a section on Resting:

Heroic though they might be, adventurers can't spend every hour of the day in the thick of exploration, social interaction, and combat. They need rest — time to sleep and eat, tend their wounds, refresh their minds and spirits for spellcasting, and brace themselves for further adventure.

Adventurers, as well as other creatures, can take short rests in the midst of a day and a long rest to end it.

It then gives us the rules for short and long rests. But it doesn't define sleep. So if your DM is not using the optional rules from Xanathar's Guide, they will have to make a ruling. I recommend using the rule from Xanathar's Guide.

Answer 2

Without the optional rules in Xanathar's, a sleeping person does not have the unconscious condition

Sleep, in fact, is not defined as a condition or state in the PHB or DMG. Rather, from the DMG "Using and Tracking Conditions" (p.248 - emphases mine)

Various rules and features in the game are clear about when they apply a condition to a creature. You can also apply conditions on the fly. They're meant to be intuitive for you to do so. For example, if a character is in a state such as sleep, that lacks consciousness, you can say the character is unconscious. Or did a character just stumble onto the ground? He or she is now prone.

Let us be clear about this passage. It does not say that sleeping characters have the unconscious condition. Rather, the point is that sometimes a DM can apply the mechanical effects of conditions 'on the fly', that is, when they feel the situation as such warrants it. In the case of sleep, it is not that a character is unconscious, but rather that they lack consciousness and thus can be treated for some situations as if they were unconscious.

This is important, because the unconscious condition imposes the following effect:

An unconscious creature is incapacitated (see the condition), can’t move or speak, and is unaware of its surroundings

A truly unconscious character is "unaware of its surroundings". The DMG is not advocating that normally sleeping characters are unable to be awoken by noise or bright flashing lights. They may be treated as blinded for their comrades walking across a dimly lit room, but perhaps not for the light from a bullseye lanthorn suddenly falling on their face. They should be treated as deafened for whispers across the room, but not for shouts. This is what the DMG means when it says that DM's need to apply the unconscious condition intuitively to a sleeping character.

If such a character is attacked without warning, the DM can "say" that the unconscious condition applies, and the attacker has advantage on their hit roll. But if a comrade shouts at the sleeping PC, the DM can then "say" that the unconscious condition does not apply and that the PC can hear the noise and awaken.

And an unconscious person is not necessarily sleeping

Sleeping does not impose the unconscious condition - sleeping is a situation for the DM to intuitively make rulings on the fly. Whether unconsciousness makes a creature a valid target for the Dream spell is a matter for a DM to rule on in a similar manner. Does your DM think that unconsciousness would permit dreaming?

For myself as a DM, I would likely make a decision based on the cause of unconsciousness. Drow poison that knocks a character out for an hour, but allows them to be shaken awake? Yeah, I can see such a character dreaming while unconscious. Body going into shock, making death saves while at 0 hp? Probably not.

Answer 3

There are three things here that are distinct but overlap: Sleep, magical sleep, and unconsciousness.

As described in Xanathar's Guide to Everything, a sleeping person has the Unconscious condition. However, just because all dogs are animals doesn't mean all animals are dogs. All sleepers are unconscious; not all unconsciousness is sleep.

Some magical effects that cause unconsciousness are specifically linked to sleep. Sometimes it's specifically sleep, sometimes it just explicitly excludes creatures that can't sleep without actually calling the condition 'sleep'. These effects generally have specific rules included as to how the sleeper can be roused -- it might be as simple as waking any normal sleeper, it might require dealing damage and lesser actions don't suffice, or it might be as complex to break as a kiss from one's true love (whatever that means).

But you can easily be unconscious without being asleep, too. The most common one is by being at zero hit points -- "beaten into a coma" is not the same thing as "asleep" (ask any doctor). A number of poisons can do the same thing, and not even injuries can rouse you. There are magical effects that can do the same thing, and generally the effect itself will tell you when it ends.

So you can be unconscious and asleep, you can be unconscious and magically asleep, you can be magically unconscious, or you can be just plain unconscious, and they all have slightly different meanings and implications.

Answer 4

If the conditions are not defined, the usual English meanings apply, and unconscious means:

in the state of not being awake and not aware of things around you, especially as the result of a head injury:

There are two forms of unconsciousness: sleep, from which people can be aroused, and coma, from which they can't be. Coma is often called "unconsciousness" and distinguished from sleep -- hence the "especially."

Therefore, a person you just knocked unconscious can't be asleep, because he can't be roused from the unconsciousness.

Which one applies must be a DM ruling in particular cases.