The Long Rest rules read:
A long rest is a period of extended downtime, at least 8
hours long, during which you sleep or perform light activity: reading,
talking, eating, or standing watch for no more than 2 hours of the
rest period. If the rest is interrupted by a strenuous activity—such
as attacking, taking damage, or casting a spell—you must start the
rest over to gain any benefit from it, unless the interruption takes
less than an hour. You must have at least 1 hit point to take a long
rest. At the end of the rest, you regain all your hit points and half
of your maximum number of Hit Dice (round up). You cannot benefit from
more than one long rest in a 24-hour period.
The elven Trance racial trait reads as:
Trance: Elves do not need to sleep. Instead, they meditate deeply for
4 hours a day. (The Common word for such meditation is “trance.”)
While meditating, you can dream after a fashion; such dreams are
actually mental exercises that have become reflexive through years of
practice. After resting in this way, you gain the same benefit that a
human does from 8 hours of sleep.
I have heard two views regarding these rules:
- An Elf can get the benefit of a Long Rest in only 4 hours.
- The 4 hours only applies to not being exhausted, 8 hours is still required get the benefits of a Long Rest.
Which is it? Please provide supporting information, possibly from previous versions.
An elf receives the benefits of a long rest in 4 hours while using the "Trance" trait.
According to the 2017 update to the Sage Advice Compendium:
This ruling reverses guidance in the earlier version of the SAC, due to errata changing the rules for long rests.
Interactions between the "Trance" trait and long rests
A long rest is defined as:
The elf's Trance trait is defined as:
Since the "Trance" trait replaces the need for sleep (which most races need in order to complete a long rest), the elf is able to satisfy the requirements of the long rest while in a semiconscious trance for four hours.