Horror RPG Systems Comparison
Different horror RPGs handle investigation, sanity, and cosmic dread in unique ways. This guide compares major horror systems to help you choose the right one for your group, or adapt elements between systems.
🦑 Call of Cthulhu (Chaosium)
System Overview
The classic horror RPG since 1981. Uses percentile-based Basic Roleplaying (BRP) system. Roll d100 under your skill percentage to succeed. Currently in 7th Edition.
Core Mechanics
- Skills: Percentile-based, roll under to succeed
- Sanity: Points from 0-99, decreases with horror
- Luck: Resource pool for re-rolls
- Mythos: Knowledge inversely related to sanity
Strengths & Weaknesses
✅ Strengths
- Extensive published scenarios
- Decades of support and community
- Detailed investigation rules
- Iconic sanity system
- Multiple time periods supported
⚠️ Weaknesses
- Can stall on failed skill rolls
- Investigator death/insanity common
- Requires Three Clue Rule implementation
- Combat often lethal
Best For
Groups who want classic Lovecraftian horror with high lethality. Perfect for 1920s investigations, one-shots, and players comfortable with character death. The gold standard for cosmic horror.
🔍 GUMSHOE (Pelgrane Press)
System Overview
Designed specifically for investigative scenarios. Core principle: if you have the right investigative skill and look in the right place, you automatically find core clues. Used in Trail of Cthulhu, Night's Black Agents, etc.
Core Mechanics
- Investigative Abilities: Auto-success for clues
- General Abilities: Point-spend for bonuses
- Stability: Mental health pool
- Narrative Focus: Keeps investigation moving
Strengths & Weaknesses
✅ Strengths
- Never stalls on missed clues
- Investigation-focused design
- Faster pacing than CoC
- Point-spend adds tactical depth
- Multiple genre variations
⚠️ Weaknesses
- Resource management can feel gamey
- Less published material than CoC
- Requires scenario design for system
- Point pools need tracking
Best For
Groups who prioritize story over mechanics. Perfect for investigation-heavy campaigns where you want guaranteed forward progress. Great for players new to investigative games.
🔫 Delta Green (Arc Dream Publishing)
System Overview
Modern-day cosmic horror where players are secret government agents fighting the unnatural. Uses d100 percentile system similar to Call of Cthulhu but with modern action-horror focus.
Core Mechanics
- Percentile Skills: Like CoC, modern skills
- Sanity: Breaking points instead of gradual loss
- Bonds: Relationships that anchor you
- Resources: Government backing with strings
Strengths & Weaknesses
✅ Strengths
- Modern setting with guns & tech
- Conspiracy thriller atmosphere
- Bond system creates drama
- More action-oriented than CoC
- Strong published scenarios
⚠️ Weaknesses
- Modern setting only
- Less cosmic scope than CoC
- Government agency focus required
- Can feel like X-Files with Cthulhu
Best For
Groups who want modern cosmic horror with conspiracies. Perfect for military/law enforcement characters, action-horror balance, and ongoing campaign with organization backdrop.
🌌 Infinite Horizons (RPGAnywhere)
System Overview
A storyteller-focused system using dice pools for success-based resolution. Features three distinct horror settings spanning different time periods. Emphasizes flexible character creation with traits and stats combining in nearly infinite ways. Learn more at rpganywhere.com/infinite-horizons
Core Mechanics
- Dice Pool: Roll multiple dice, count successes
- Traits + Stats: Flexible combinations for any action
- Stress & Trauma: Mental health system
- Narrative Focus: Story-driven resolution
Three Horror Settings
- Occultis Mechanica: Steampunk eldritch horror
- Whispers of the Frontier: Old West occult mysteries
- Terra Vista: Modern day (Stranger Things/Scooby Doo vibes)
Strengths & Weaknesses
✅ Strengths
- Extremely flexible character options
- Three distinct horror time periods
- Narrative-focused mechanics
- Adaptable tone (cosmic to pulpy)
- Dice pool system easy to learn
⚠️ Weaknesses
- Newer system with growing material
- Requires more GM creativity
- Less established community
- Players need narrative buy-in
Best For
Groups who want flexibility in both mechanics and setting. Perfect for GMs who enjoy creative storytelling, players who like character customization, and tables that want to switch between steampunk, Old West, and modern horror without changing systems.
📊 Quick Comparison
| Feature | Call of Cthulhu | GUMSHOE | Delta Green | Infinite Horizons |
|---|---|---|---|---|
| Clue Discovery | Roll to find | Automatic | Roll to find | Narrative/Dice pool |
| Lethality | Very High | Moderate | High | Moderate |
| Sanity System | Gradual loss | Stability pools | Breaking points | Stress & Trauma |
| Setting | Multi-era | Multi-genre | Modern only | Three eras |
| Complexity | Medium | Medium-High | Medium | Lower |
| Scenarios Available | Extensive | Moderate | Good | Growing |
| Best For | Classic Lovecraft | Story-first | Modern action-horror | Flexible storytelling |
🎲 System-Agnostic Horror Tips
These principles work regardless of which system you use:
Investigation
- Always use Three Clue Rule
- Multiple paths to every truth
- Accept creative solutions
- Failed rolls ≠ no information
- Keep investigation moving forward
Horror Atmosphere
- Show don't tell when possible
- Build dread through anticipation
- Use all senses in descriptions
- Less is more with monsters
- Focus on cosmic insignificance
Sanity/Stress
- Consequences for mental trauma
- Allow recovery between scenarios
- Make insanity meaningful, not just mechanical
- Tie phobias to character backstory
- Don't overuse - preserve impact
Pacing
- Balance investigation and horror
- Provide breathing room between scares
- Build to crescendo, don't plateau
- End sessions on cliffhangers or victories
- Vary investigation locations and methods
💡 Choosing the Right System
Decision Guide
Choose Call of Cthulhu if:
- You want classic Lovecraftian horror
- 1920s or other historical periods interest you
- You have extensive published scenarios available
- Your group is okay with high character lethality
Choose GUMSHOE (Trail of Cthulhu) if:
- Investigation is your primary focus
- You want guaranteed clue discovery
- Your group values story over crunch
- You're new to investigative games
Choose Delta Green if:
- You want modern-day cosmic horror
- Military/government agents appeal to your group
- You like conspiracy thriller elements
- More action-oriented horror is preferred
Choose Infinite Horizons if:
- You want maximum flexibility in character creation
- Your group enjoys narrative-focused mechanics
- You want to explore steampunk, Old West, or modern horror
- You prefer dice pool systems
- You like switching between horror tones without changing systems