One With Nightmares

You may concoct an edible creation, mixture, or tonic that relaxes your nerves or deadens your mind using Alchemist Supplies or an Herbalist Kit.  This Restful Concoction gives you +2 to your attempt in getting A Good Night's Sleep.

If you are to venture into your Nightmares willingly, you and your party will need a dose of Dream Elixir.  You can craft this with your background tool of choice, but you will require special herbs from a shaman or other appropriate source - likely involving a side quest.  The mixing of this Dream Elixir will also require you to pass a Medicine check of at least DC 18, as you need to understand how to mix these herbs and items successfully.  One vial of Dream Elixir is enough for four - including yourself - to be pulled into your Nightmares.  Your DM may add additional requirements in the creation of a Dream Elixir, such as requiring at least one hour of ritual chanting.

If you fail to get A Good Night's Rest at least three times in a row, you suffer from any of the following choices, at the discretion of you or your DM:

• You regain none of your spent Spell Slots until your next successful Long Rest.
• You regain half of your spent Spell Slots, and you take a -4 penalty to your Saves for the day until your next successful Long Rest.
• You and your party are pulled into a Nightmare.  At the DM's discretion, death in this Nightmare is death in real life.  In order to break free of this Nightmare, you or your party must successfully realize that it is a Nightmare (Wisdom Save DC 10 or higher) or complete the encounter.  The DM may also
• Your every waking moment until your next successful Long Rest is haunted by lost spirits and visions of the damned, or whatever your particular flavor of Horror chooses.  You take a -4 to your Perception, -2 to your Insight, -2 to any roll for remembering information, and -1 to all your Saves.

If your party has become involved in a Nightmare, the party members cannot escape unless they succeed on a Wisdom saving throw (DC 12 or DM's discretion) or complete the encounter.  Completing the encounter does not necessarily mean surviving the encounter.  It is the DM's discretion as to whether death in this Nightmare is death in the campaign and what "completing" the encounter may necessitate.  It is also the DM's discretion as to what content is in this Nightmare - it could be anything.

Once inside a Nightmare, your party cannot escape through conventional means.  This Nightmare could be anything from a combat encounter to a demented puzzle room or anything in-between.  In order to escape, you must either complete the encounter or die.  Everyone who dies in the encounter, whether by death fails, total party kill, or conditional failures will only regenerate half of their spell slots (rounded down) upon waking.

While inside the dream, each party member may make a Wisdom saving roll (DC 12).  On success, they gain a benefit as decided by the DM.  This could be the ability to snap the party out of the Nightmare entirely (whether literally or by banishing a combat encounter in progress), or otherwise gaining a boon that gives them an advantage (advantage on to-hit rolls, or passing through locked doors for example).

You may embark on a side quest, at your DM's discretion, on a side quest to engage with and banish the horrors that lie within.  This could be a matter of making a special Dream Elixir that lets you and your party willingly engage with the echoes of your mind and the horrors within, or traveling to a domain or plane in which the Horror plaguing you exists.

Should you break the cycle that your personal Horror has inflicted upon you, you are no longer bound to the issues that it plagued you with.  You no longer struggle to gain A Good Night's Sleep and your Sleep Deprivation will be cured on your next Long Rest.