General idea

Objectives:

• Big inspiration comes from OSR D&D, but this is run on a computer, so we don't need to abstract as much to run things quick and smoothly.
• HUD diagetic - no bars, show damage and status by how you're moving, bloody, dripping blood, shivering, heavy breathing, etc.
• Avoid Rambo Doomguy Syndrome - you can't get hosed down by a minigun and still keep fighting with a low HP bar. Without 'magic', wounds can be quickly dangerous or lethal, and sometimes can't be healed within the hours-long time period of this game.
• Fun > Realism, but as much realism as possible to be able to make predictions based on common knowledge
• Do not abstract mental traits such as attention, intelligence, charisma, memory - these are for the player to provide

Putting something together

Maybe have 'Luck' as an avoidance of lethal damage, aka plot armor, omens - luck can be like enemy weapon doesn't fire, hangfires, jams, or shot goes wide, cultist says 'boo' instead

Status/Damage modeling

(each of the below can have a corresponding 'resistance' level (maybe as a status effect) that can be improved by feats, various consumables & spells, etc)

Oxygen/stamina - larger than Dark Souls, takes longer to recharge, more like CDDA, everything slows down as this goes down; max lowered by pain and blood loss. Physiologically? VO2 max, lactate threshold, efficiency (performance per VO2).

Pain - affects with a delay of about one second, gives maluses to many aspects such as speed, increases rate of stress gain; lowers over time, by painkillers, by treating source; maybe only have greatest pain source matter. High levels produce distracting visual and audio effects like fisheye vision, red around edges, pulsing brightness in vision, seeing stars, whiteout, tinnitus, pounding pulse in ears, or other annoying noises, etc

Blood loss - increases risk of suffering shock, leading to death; very slow regen or maybe only in saferoom, perhaps requiring food and water (how to show blood loss level diagetically? the red pulsing screen edges fisheyeing inwards towards enter of screen?; whiteout?; erratic and louder heartbeat? (conflicts with stamina); momentarily micro-blackouts?; blood splotches on body when look down?)

Stress - Infra Arcana-style shock that continues to go up while not in a well-lit area, increases further when hurt or very close to fearsome things; when maxes, gain a (random or perhaps appropriate) mental trauma and reset Stress gauge - continuing to get them will lead to the run being less and less viable; maybe roll from a random list that adds stress level so it gets to more and more serious results ala Aliens RPG; lowered by fountains, going down stairs to new level, major story objective success, saferoom

Statuses (Injury/Trauma (physical and mental)) - typically maluses (sometimes buffs) such as:

• Blinded & partially
• Deafened & partially
• Frightened/morale broken
• Grappled
• Incapacitated
• Invisible
• Paralyzed
• Petrified
• Poisoned/Nausea - burping noise, must stop to vomit randomly, possible constant HP loss, etc
• Smoke inhalation - stamina affecting
• Prone (Downed)
• Restrained - web, strong grab, bear trap, etc
• Stunned - staggered
• Unconscious
• Exhaustion
• Confused
• Charmed
• head wound - Tinnitus and somewhat deaf or Lower sight radius or blurry at a distance, confusion or wobbly movement
• shoulder wound - aiming penalty (shoulder wound chance on firing 2-bore)
• arm wound - wound that makes aiming worse
• hand wound - wound that makes reloading and inventory actions take longer, firearms less accurate, melee weapons more likely to be dropped
• leg wound - slows you down, can't jump
• foot wound - slow you down, causes to trip and fall sometimes
• broken bones - effectively permanent across run, some would be run-ending
• tremors
• baleful polymorph
• on fire - typically sub-optimal
• bleeding - continual damage until dealt with, chance to stop over time
• fresh/well-rested
• adrenaline - can shrug off minor and moderate wounds for a time
• hasted - movement speed, all action speeds, and mouse turn rate OR game other than player runs slower
• slowed - movement speed, all action speeds, and mouse turn rate OR game other than player runs faster
• hungry/thirsty - slower stamina regen, lower max (for GDIAH, we're not going to have this)
• rage/angry
• corrosion - small DoT, equipment damage chance
• hallucinating
• suffocating/drowning - constant drain of oxygen/stamina
• turning into green slime - very bad indeed
• teleportitis
• mute - can't talk nor use scrolls
• 'Spellbound': can act, but cannot move
• damage resistances and status immunities
• dead - the ultimate debuff

Body parts

Bodyparts and armor layering CDDA style

• Head: "head_forehead", "head_crown", "head_nape", "head_throat", "head_ear_r", "head_ear_l"
• Eyes: "eyes_left", "eyes_right"
• Mouth: "mouth_lips", "mouth_nose", "mouth_cheeks", "mouth_chin"
• Arms: "arm_shoulder_l", "arm_upper_l", "arm_elbow_l", "arm_lower_l"
• Hands: "hand_wrist_l", "hand_palm_l", "hand_back_l", "hand_fingers_l"
• Legs: "leg_hip_l", "leg_upper_l", "leg_knee_l", "leg_lower_l", "leg_draped_l"
• Feet: "foot_sole_l", "foot_arch_l", "foot_toes_l", "foot_ankle_l", "foot_heel_l"

Loose notes

Fatigue, Composure (Poise, Pain, Shock, etc), Blood

Trophy Dark's Ruin - more suited to the sanity system (spoilery)

Doom
Luck reduces a Doom
Luck and Doom as a Victory/Defeat track

Dread
Despair

"Something I've really been into is combining exhaustion, damage, and encumbrance. I've settled on using Item slots. Which are filled with your equipment, supplies, spells, mutations, tiredness, and wounds. If you take a Wound the item in that slot either breaks, drops to the ground, or is rendered inactive. If you place exhaustion in a slot you simply drop the item to the ground or cannot make any action except lurch forward. If all of your slots are filled with any combination of exhaustion and at least half Wounds, you die.
Knave does this, and several GLOGhacks (Bonepunk and Catacombers to name a few) that I've taken a shine to.
Cards for penalties, statuses can take up slots, like Maus or whatever.
It’s okay that chars can’t carry much, they need to be super light for mobility, climb ropes, jump gaps, dodge, etc"

• neat in tabletop but perhaps unnecessarily abstracted for a video game

"In OD&D, a normal man has 1-6 hit points, and all weapons do 1-6 hit
points of damage. In other words, the average man can be slain with a
single damage roll from any weapon. This makes perfect sense given
D&D's abstract system: a dagger thrust can kill you just as readily as a
chop from a greataxe. When describing OD&D combat, I only describe
severe or mortal wounds when the last 6 hit points are reached. Prior to
that, damage is described as near-misses, parried blows that would've
slain a lesser warrior, scratches, bruises, et cetera. This means that
players can get a sense of how tough and skilled an enemy is by the
effect their damage rolls have. If the PCs have dished out 14 points of
damage, and I'm describing how the bad guy just got nicked on his
forearm and is starting to sweat, they know that this guy has some
serious hit points. On the other hand, if the first four points of damage
they inflict opens a gaping, bleeding wound and their foe cries out in
anguish, they know this probably isn't an 8th level superhero they're
fighting."

falling damage - basically break bones, potentially back, be unable to stand, drop what you're holding, potentially be forced to quit the game instead of outright being killed

taking damage (just underwater?) risks letting out some breath/stamina

Thoughts on luck as a mechanic

?
Player Protected by worn ward which don't realize wearing til later (could explain luck)
?
Sacrificing something of value at the safe room altar gives a chance of giving luck back

Luck, have a section where you have to give it up, have to leave it eventually, or maybe even the use of luck items at all is curseable magic (of the 'you can enter but not leave' type
The Night that Speaks, strong will to face and clear the dungeon

no luck? cultists very deadly in Act 1?
slow burn

luck a form of hypergeometry? thus affecting [REDACTED]?