Just came up with an idea for a mechanic for homebrew. Some spells or abilities could do "secret damage" of various types. This is an amount of damage done to a player, such that when their hit points become less than or equal to the amount of secret damage they've taken, they fall unconscious. But only the DM knows how much cumulative secret damage each creature has taken.
It might be possible to resist or be vulnerable to secret damage. It's up to the DM whether or not to tell the player whether their character knows they're resistant or vulnerable.
This can be a way to inject more drama and uncertainty into a battle, as later in the battle, they won't know how close to death they are, no matter how much other damage they've taken, especially if they've been recently told they were hit by some kind of damage they're vulnerable to. They'll have to take risks rather than play it safe. Rather than assuming the paladin has plenty of hit points and you can conserve your high level healing spells, you might have to spend that spell slot. You don't know if another hit from that dragon fire could kill them outright.
In terms of realism, I think it's actually very reasonable that most forms of psychic damage are secret damage. It's just a loss of confidence that makes you wear down more easily. Necrotic damage also makes sense. Your body doesn't have nerves in every organ, and some can be very diseased without you knowing it. I think it can also work for bludgeoning, force, and thunder damage. There are the occasional stories of people taking hits that show little damage at first, but actually damaged internal organs. Boxers who walk out of the ring victorious and fall dead 10 minutes later. Or 10 years. You could even have permanent secret damage to a PC's max hp. The player might never suspect until they go down at 2 hp. (As the DM, subject to any session 0 discussion about fudging, you could even choose the exact amount of permanent secret damage on the fly later when it creates a dramatic moment.)
Cold damage can feel numb. Poison can be slow acting (1d4 per round secret poison damage; you'll probably go unconscious a few rounds after the end of the battle).
This is pretty cool, It probally only works in the campaigns in the middle ground between "mostly story filled game, mechanic light" and 1E style punishing dugeon delve.
Just came up with an idea for a mechanic for homebrew. Some spells or abilities could do "secret damage" of various types. This is an amount of damage done to a player, such that when their hit points become less than or equal to the amount of secret damage they've taken, they fall unconscious. But only the DM knows how much cumulative secret damage each creature has taken.
It might be possible to resist or be vulnerable to secret damage. It's up to the DM whether or not to tell the player whether their character knows they're resistant or vulnerable.
This can be a way to inject more drama and uncertainty into a battle, as later in the battle, they won't know how close to death they are, no matter how much other damage they've taken, especially if they've been recently told they were hit by some kind of damage they're vulnerable to. They'll have to take risks rather than play it safe. Rather than assuming the paladin has plenty of hit points and you can conserve your high level healing spells, you might have to spend that spell slot. You don't know if another hit from that dragon fire could kill them outright.
In terms of realism, I think it's actually very reasonable that most forms of psychic damage are secret damage. It's just a loss of confidence that makes you wear down more easily. Necrotic damage also makes sense. Your body doesn't have nerves in every organ, and some can be very diseased without you knowing it. I think it can also work for bludgeoning, force, and thunder damage. There are the occasional stories of people taking hits that show little damage at first, but actually damaged internal organs. Boxers who walk out of the ring victorious and fall dead 10 minutes later. Or 10 years. You could even have permanent secret damage to a PC's max hp. The player might never suspect until they go down at 2 hp. (As the DM, subject to any session 0 discussion about fudging, you could even choose the exact amount of permanent secret damage on the fly later when it creates a dramatic moment.)
Cold damage can feel numb. Poison can be slow acting (1d4 per round secret poison damage; you'll probably go unconscious a few rounds after the end of the battle).
This is pretty cool, It probally only works in the campaigns in the middle ground between "mostly story filled game, mechanic light" and 1E style punishing dugeon delve.
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