Sleep (5e Variant Rule)
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In the Core Rules, players can recover all hit points during a long rest, which takes eight hours, and regain hit points by rolling hit dice during a short rest, which takes one hour. This variant rule means to make these core rules more realistic, but this is all coming from my head, no research done. Too lazy for that. Shall we continue?
A long rest can now vary from six hours to twelve hours, and characters gain different levels of benefits depending on how much sleep they get. The rules for when a character doesn't sleep in a 24 hour cycle is still the same, found in XGtE on page 77. Also, this variant rule takes into account the Slow Natural Healing option rule found in the DMG on page 267. The rules for a short rest stays the same.
A character must completely sleep for at least six hours in order to gain any benefits. When a character does so, refer to the details below for the effects from the length of the character's sleep. The character gains benefits from 6 hours all the way up to the length ofthe character's sleep. For example, a character who has slept for 9 hours gain the benefits for 6 hours, 7 hours, 8 hours, and 9 hours.
- 6 hours
You regain half your hit dice.
- 7 hours
You regain uses of any features and traits that recharges after finishing a long rest. This also applies to anything else that works by a similar recovery mechanic (some magic items, some feats and epic boons, etc.).
- 8 hours
You can recover hit points as normal through the Slow Natural Healing variant rule. You can also remove one condition that is afflicting you, and you also recover one exhaustion level, if any.
For each additional hour you rest, you can remove one more condition afflicting you.
For elves, they only need to rest for half as long in order to gain the corresponding benefits (i.e. being in a trance for three and a half hours will allow the elf to regain half their hit dice and regain uses of features and traits).