Call of Cthulhu vs Unknown Armies
Compare Call of Cthulhu and Unknown Armies side by side. See differences in complexity, dice, genre, cost, and more.
| Call of Cthulhu | Unknown Armies | |
|---|---|---|
| Genre | Horror, Modern | Horror, Modern |
| Tags | Investigation, Fear & Stress Mechanics, Mystery, Deadly, Corruption, Skill-Based, Atmospheric, One-Shot Friendly, Character-Driven, Narrative | Urban Fantasy, Weird, Noir, Fear & Stress Mechanics, Character-Driven, Sandbox, Worldbuilding, Freeform Magic, Strong GM Support, Lore-Heavy |
| Core Mechanic | Roll d100 equal to or below a skill or characteristic. Hard and Extreme tests use half and one-fifth of that rating. Bonus and penalty dice select a better or worse tens digit. Eligible failed skill rolls can be pushed by taking further action, risking a harsher consequence. | Roll percentile dice against an identity or ability rating and succeed on a result equal to or under it. Doubles make a matched success or matched failure, 01 is a critical success, and 00 is a fumble. Rolls with an identity tied to a character's obsession can be flip-flopped, swapping the two dice so that 54 reads as 45. Each relevant passion normally allows one more flip-flop per session. |
| Dice | d100 | d100 |
| Complexity | Medium | High |
| Accessibility | High | High |
| Runnability | Very High | Very High |
| License | Chaosium Fan Material Policy | All Rights Reserved |
| Third-Party Publishing | Commercial publishing allowed — Community content program | Noncommercial only — Atlas Games Fair Use policy |
| Summary only, not legal advice. Check current terms before publishing. | ||
| Cost | $$ | $$ |
| Publisher | Chaosium | Atlas Games |
| Year | 2014 | 2017 |
| Languages | English, French, German, Italian, Japanese, Korean, Spanish, Polish, Portuguese, Russian, Swedish, Chinese | English, Spanish |
| Best For | Groups who want clue-driven horror with ordinary investigators and lasting consequences. Suits focused mysteries and campaigns where survival matters more than defeating every threat. | Groups who want occult horror in the present day, where each character's obsessions and trauma and the cabal's shared goal drive the campaign instead of a prepared plot. It suits tables comfortable with violence, madness, and transgressive magick, and with building their own local setting together in the first session. |
| Highlights | Pushing a failed roll offers another chance at the goal with a more serious consequence if it fails. Learning Mythos lore reduces maximum Sanity, tying useful knowledge to lasting vulnerability. An Idea roll gets a stalled investigation moving again, with failure putting investigators into danger. | In ordinary play, each hardened notch on the shock gauge moves five points from an upbeat ability such as Connect to its paired downbeat ability such as Struggle. Adepts charge their school of magick through its own obsessive behavior and lose all the charges they are holding when they break its taboo. The cabal pursues a player-chosen objective tracked in percentiles, and intense milestones earn bigger rolls toward it than petty ones. |
| Considerations | A major wound can leave an investigator dying, making direct confrontation dangerous. Bouts of madness temporarily place investigator actions under Keeper control. Foot and vehicle chases track relative speed and movement actions, adding a separate procedure to pursuit scenes. | Violence, madness, abuse, and transgressive magick are core subject matter, so the group needs to agree on limits before play. Many firearms can kill a character with the default wound threshold of 50 in one hit. Twenty-five or more hardened notches normally burn a character out, which shuts off passion flip-flops and avatar identities until the character gets treatment. |