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Apocalypse Keys vs Call of Cthulhu

Compare Apocalypse Keys and Call of Cthulhu side by side. See differences in complexity, dice, genre, cost, and more.

Apocalypse KeysCall of Cthulhu
GenreHorror, ModernHorror, Modern
Play StylePlaybook-Driven, Mystery, Investigation, Corruption, Drama, Fiction-FirstInvestigation, Deadly, One-Shot Friendly, Atmospheric, Roleplay-Heavy, Mystery, Horror, Corruption, Skill-Based
Core MechanicRoll 2d6 and spend Darkness Tokens (up to 3) to add to the result instead of a fixed stat modifier. 7 or less is a miss, 8–10 is a complete hit, and 11+ is a catastrophic success: you achieve your goal but your monstrous power causes collateral damage. Bonds with other characters add +1 or −1. Darkness Tokens accumulate through roleplaying triggers specific to each playbook; exceeding 5 tokens forces a crisis that costs either a Bond or advances your Ruin track toward becoming a Harbinger of the apocalypse.Roll d100 equal to or under your skill percentage. Success tiers at half (Hard) and one-fifth (Extreme) of the skill value. Bonus and penalty dice adjust the tens digit. Failed rolls can be pushed for a second attempt at greater risk.
Dice2d6d100
ComplexityLowMedium
AccessibilityMediumHigh
RunnabilityHighVery High
LicenseCC BY-SA 4.0 (text)Chaosium Fan Material Policy
Cost$$$$
PublisherEvil Hat ProductionsChaosium
Year20232014
Best ForGroups who want emotionally intense, mystery-driven play as monstrous agents investigating apocalyptic threats: where the real tension comes from relationships and the risk of losing yourself to your own power.Investigation-driven horror where combat is deadly and sanity is fragile. Great for one-shots.
HighlightsDarkness Token economy replaces static stats with a dynamic risk/reward resource that escalates tension throughout play. Catastrophic success mechanic means the strongest rolls carry the most dangerous consequences. Seven playbooks built around emotional wounds rather than combat archetypes. Five pre-assembled mysteries plus detailed guidance for creating custom ones.Tracking Sanity as a depletable score ties mental erosion to the fiction, so confronting cosmic horror mechanically wears characters down. The percentile skills resolve on a d100 roll-under, with Hard and Extreme bands at half and one-fifth of the rating. Bouts of Madness convert failed Sanity checks into temporary phobias, manias, or loss of character control.
ConsiderationsRequires buy-in for emotionally vulnerable roleplay: characters are designed to hurt and be hurt. No tactical combat system; conflict resolution is narrative. Mysteries have no pre-written solutions, which demands improvisational confidence from the Keeper. Mature themes including body horror, mind control, and moral degradation are baked into the core premise.The chase rules add a detailed positioning subsystem whose complexity outweighs how often it sees use. Character creation allocates points across a long list of skills, a slow first step for new players. In long campaigns the sanity spiral can strip a character of player control as madness accumulates.