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Horror Campaign Addendum

Specific Guidance for Running Librus Nocturnum

Creating Horror Atmosphere

Environmental Storytelling

  • Foreshadowing: Dead animals, wilted plants, fleeing wildlife
  • Wrong Details: Too many doors, stairs that go nowhere, windows showing wrong views
  • Sensory Unease: Metallic taste in air, feeling of being watched, shadows moving wrong
  • Temperature: Sudden cold spots, breath visible indoors, frost in summer

Pacing Horror

The Horror Curve

Normal → Unease → Dread → Reveal → Panic → Resolution
  1. Normal (5-10 min): Establish baseline comfort
  2. Unease (10-15 min): Something's off but unclear
  3. Dread (15-20 min): Clear danger, unknown source
  4. Reveal (5 min): Monster/threat exposed
  5. Panic (10-20 min): Fight/flight/freeze
  6. Resolution (5-10 min): Escape or victory

Using Game Mechanics for Horror

Exhaustion as Fear

When PCs experience terror: - Witnessing horrific death: 1 level exhaustion (CON save DC 10) - Supernatural horror: 2 levels (WIS save DC 15) - Cosmic horror: 3 levels (INT save DC 20)

Remember: Exhaustion in 2024 = -2 per level to all d20 rolls

Limited Resources

  • Count torches/lantern oil
  • Track rations
  • Spell slots don't refresh easily
  • Long rests might be interrupted

Modified Death Saves

For horror tone: - Fail on 9 or less (instead of 10) - Natural 1 = 2 failures + lingering injury - Describe each failed save (cold creeping in, vision fading)

Curses & Contagions (DMG 2024)

Quick Curse Generator

Trigger (d6): 1. Defiling sacred ground 2. Breaking a promise 3. Stealing from the dead 4. Reading forbidden text 5. Spilling innocent blood 6. Denying hospitality

Effect (d6): 1. Can't benefit from healing magic 2. Vulnerability to one damage type 3. Disadvantage on saves vs fear 4. Must pass WIS save to long rest 5. Max HP reduced by 1d4 per day 6. Haunted by spirits only they see

Removal: - Make amends for the transgression - Find and destroy curse's source - Complete a ritual at specific location - Remove Curse suppresses for 24 hours only

Demonic Possession (DMG Rule)

  • Target: CHA save DC 15 or possessed
  • Trigger: Rolling a 1 on any d20
  • Effect: Demon controls character
  • Recovery: CHA save DC 15 at turn end
  • Long-term: Save after long rest to end

Librus Nocturnum Specific Tips

Session Structure

  1. Start Normal: 10 minutes of regular D&D
  2. First Sign: Something minor but wrong
  3. Investigation: Let them explore the threat
  4. Escalation: Things get worse if ignored
  5. Confrontation: Face the horror directly
  6. Aftermath: Consequences and scars

Making Monsters Scary

The Unknown

  • Don't name it immediately ("the thing", "the creature")
  • Describe effects, not appearance ("something tears the door off")
  • Use partial glimpses (claws, eyes, shadows)
  • Different each time they see it

The Unstoppable

  • First encounter: They can't hurt it
  • Must find weakness through investigation
  • Environmental solutions (trap, banish, seal)
  • Running is valid option

The Personal

  • Uses PC backstories against them
  • Mimics loved ones' voices
  • Knows their secrets
  • Attacks what they value

Horror Safety Tools

The X-Card System

  • Place card with X in center of table
  • Anyone can tap it to stop current content
  • No questions asked, scene changes
  • Discuss privately after session if needed

Lines and Veils

Lines (never cross): - Harm to children/animals - Sexual violence - Specific phobias (player-defined)

Veils (fade to black): - Torture details - Body horror - Psychological trauma

Check-Ins

Between scenes ask: - "Everyone good to continue?" - "Too intense or just right?" - "Need a break?"

Running Horror Combat

Make It Desperate

  • Monsters regenerate
  • Reinforcements arrive
  • Environment becomes hostile
  • Escape routes close

Describe Injuries

Instead of: "You take 8 damage" Try: "Its claws rake across your chest, tearing through armor. Blood soaks your shirt."

Use Lingering Injuries (Optional)

When dropped to 0 HP: 1. Scarred: Disadvantage on CHA checks for 1 week 2. Shaken: Frightened of similar creatures for 24 hrs 3. Wounded: Speed -10 ft for 3 days 4. Traumatized: Nightmare prevents long rest (WIS save DC 10)

Quick Horror Encounters

The Thing That Follows

  • Always 60-120 ft behind
  • Matches party speed exactly
  • Doesn't respond to attacks
  • Gets closer each night
  • Resolution: Must be faced alone

The Wrong Room

  • Door leads somewhere impossible
  • Geography doesn't match
  • Exit disappears
  • Must solve puzzle to escape
  • Time passes differently inside

The Perfect Copy

  • NPC is replaced by doppelganger
  • Knows everything original knew
  • One tiny detail is wrong
  • Party must identify impostor
  • Real person found dead later

Your Horror Toolkit

Phrases That Build Dread

  • "You notice..." (then pause)
  • "Everything goes quiet"
  • "Make a Perception check" (for nothing)
  • "That's... interesting" (after any roll)
  • "Are you sure?"
  • "You can certainly try"

Environmental Effects

Roll d6 when tension needed: 1. Temperature drops 20 degrees 2. All flames dim to candles 3. Echoes stop working 4. Shadows point wrong direction 5. Animals go silent 6. Metallic taste in mouth

NPC Reactions

How locals act around horror: - Won't discuss after dark - Cross themselves/ward signs - Board windows at sunset - Children kept indoors - Strangers blamed for troubles - Old-timers know but won't tell

Session Zero Reminders

You already established: - Permadeath is real - Horror themes expected - Player buy-in achieved

Now reinforce: - Safety tools available - Horror is collaborative - Running is sometimes smart - Fear makes heroes heroic

Managing Horror Fatigue

Signs Players Need Break

  • Jokes during tense moments
  • Checking phones more
  • Less engaged with descriptions
  • "Let's just fight it"

Solutions

  • Comic relief NPC
  • Safe haven location
  • Victory against minor threat
  • Treasure/reward interlude
  • Switch to investigation/social

Your First Horror Session

Checklist

  • Dim lights/candles if possible
  • Quiet background music/ambient sound
  • Water for dry throat (you'll talk more)
  • Safety tools explained
  • Bathroom break before intense scenes

Opening Lines

Pick one: - "The inn is warm, comfortable, and completely normal... for now." - "You've been traveling for three days. Tonight feels different." - "The letter said urgent. It didn't say dangerous." - "Everyone in town seems friendly. Too friendly."

First Horror Beat

Wait 20 minutes, then: - Animal reacts fearfully to nothing - NPC mentions "it happened again" - Something everyday is slightly wrong - PC notices they're being watched - Sound that shouldn't exist here

Remember

Horror works because players care about their characters. You've built that connection in Session 0. Now:

  1. Threaten what they value
  2. Isolate them from help
  3. Escalate gradually
  4. Release tension occasionally
  5. Reward bravery

Your players want to be scared in a safe space. You're providing that experience.

"The oldest and strongest emotion of mankind is fear, and the oldest and strongest kind of fear is fear of the unknown." - H.P. Lovecraft

Quick Reference Cards: Print these for your screen: - Horror phrases list - Environmental effects table - X-card reminder - Exhaustion levels (-2 per level in 2024) - Curse effects table