How does the Sending spell interact with sleeping targets?

Question

A wizard casts Sending on a target creature who happens to be sleeping at the time.

You send a short message of twenty-five words or less to a creature with which you are familiar. The creature hears the message in its mind, recognizes you as the sender if it knows you, and can answer in a like manner immediately.

What happens? Some possibilities off the top of my head:

1. The creature is asleep, and so does not hear and cannot respond to the message.
2. The creature is awakened by the message in its mind, and once awake hears it and can respond to it.
3. The creature is not awakened by the message, but hears and can respond to it perfectly lucidly despite still being asleep.
4. The creature is not awakened by the message, does hear it, but is asleep so cannot process it lucidly. Thus they might not remember the message and might respond to it with the mutterings of a sleeping person ("Five more minutes Grandma Frog").

Answer 1

DM's choice

There is no specific rule for this, or it would say so in the spell description. All it says it that the creature hears the message in its mind, which for the purposes of being asleep wouldn't be that different from somebody speaking to you while sleeping.

Though there is an argument that the sleeping creature is more likely to remember and consciously register the words since the creature definitely "hears the message".

Whether this is enough to wake them... I think a DM would just have to either decide whether the creature is a light enough sleeper or possibly allow some kind of check (a Wisdom check?).

I would also say that they would have to be awake and conscious to reply "in a like manner" since you cannot take actions while asleep.*

*Unless replying "five more minutes, Grandma Frog" would be funnier, of course.

Answer 2

There is no official answer

It would be up to each individual DM to decide how to handle this situation. Other possibilities include:

• The spell fails as the recipient cannot receive the message.
• The spell delivers the message, but the recipient only becomes aware of it when they properly awaken.
• The spell delays delivery of the message until the recipient is capable of receiving it.