Clearly what the world needs is another fear/horror system for D&D. This one popped into my head thinking about Ravenloft.

In general, my current thinking on fear systems in games is that being afraid should be a penalty to action as an incentive to flee, but should not take away control of the PC and force particular actions. The Frightened condition in 5e, while a useful shorthand that I’ve used for this system, may be a little too far on the forcing action side since it prevents approaching the source of fear, but I think it’s workable with the attached horror subsystem.

Fear

Certain terrifying creatures (and some scary/horrifying situations) inspire Fear by being encountered. Upon seeing (or otherwise becoming aware of) the creature/source, all encountering characters must make a Fear save. The DC is equal to 10 + the creature’s CR (for games where fear is a very real difficulty) or half that total (for games where fear is more of an occasional issue). Non-creature situations should have an equivalent scale.

A Fear save is made as the player’s choice of an Intelligence, Wisdom, or Charisma saving throw based on chosen tactic:

  • Denial (Intelligence): You rationalize or compartmentalize the worst aspects of the creature, using sheer brainpower to imagine the threat as something less terrifying. This tactic is the best choice (of several bad choices) for truly unnatural creatures (like aberrations) and horrors from beyond, and grants advantage in those situations.
  • Perspective (Wisdom): You think of how big the world is and how, in the grand scheme of things, the creature is just another thing to encounter, no different than any other threat. This tactic is the best choice for supernatural (but not unnatural) creatures (like fiends, fey, and undead) and divine situations, and grants advantage in those situations. (If your world’s cosmology suggests that undead aren’t created by the divine for some reason, they may fall better under Denial).
  • Courage (Charisma): You just decide that fear is not an option, and muscle through based on sheer force of will. This tactic is the best choice for natural creatures (like monstrosities and dragons) that are just scary due to their ability to inflict serious pain, as well as more natural sources of horror (such as grisly murders), and grants advantage in those situations.

If the Fear save is failed, the character suffers the Frightened condition toward the trigger until the creature is killed, a point of Horror is accepted (see below), or the situation is escaped and everyone has a chance to cool off (which may require a short rest, at the GM’s option).

Characters may take a point of Horror as a free action to override the Frightened condition (taking long term mental trauma to overcome short term inability to act). By taking a point of Horror, the character is not subject to making additional Fear saves against the trigger or the same type of creature until the next sunset.

Characters can choose any tactic for the situation (but may not truly know whether it’s natural, supernatural, or unnatural before rolling), but likely use their highest save as their preferred tactic.

Horror

Characters gain Horror by overcoming Frightened (as described above) and by suffering a Horror trigger.

Common Horror triggers are:

  • Domination (Intelligence, Wisdom): For the strongest minds, losing control of one’s own mental processes is the most horrifying situation. Whenever you suffer the Charmed condition or are otherwise unable to act on your own volition due to mental compulsions, take a point of Horror.
  • Mutation (Charisma, Constitution): For those possessed of great beauty and health, horrors of the body can strike deepest. Whenever you suffer the Poisoned condition for a minute or longer, a disease for a week or longer, or are subjected to unwelcome polymorph or other shapeshifting effects, take a point of Horror. (Only one point of Horror for one poison or disease, even if it is ongoing for quite some time.)
  • Restraint (Dexterity, Strength): For those used to relying on their strength and mobility, being trapped is a profound phobia. Whenever you suffer the Paralyzed, Petrified, or Restrained condition (with nothing you can do through your own physical means to try to free yourself), take a point of Horror.

GMs may choose to define other phobias as additional Horror triggers. At the GM’s option, players may choose to remove a point of Horror by taking a new permanent Horror trigger. It is up to the GM whether all PCs start with one Horror trigger, or only gain them in play (which will usually require failing enough Fear saves to start needing to remove Horror points). It’s also up to the GM whether mental therapy in downtime can remove triggers.

For the most basic way to implement this system, Horror points are equivalent to levels of Exhaustion (and stack with them). At the GM’s option, a separate Horror track that works similar to Exhaustion may be created.