Call of Cthulhu vs The Derelict Speaks

Compare Call of Cthulhu and The Derelict Speaks side by side. See differences in complexity, dice, genre, cost, and more.

	Call of Cthulhu	The Derelict Speaks
Genre	Horror, Modern	Scifi, Horror
Play Style	Investigation, Deadly, One-Shot Friendly, Atmospheric, Roleplay-Heavy, Mystery, Horror, Corruption, Skill-Based	Rules-Light, One-Shot Friendly, Horror, Character-Driven, Deadly, Low-Prep, Theater of the Mind, Open Source
Core Mechanic	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.	When a Speaker opposes a Responder, the player rolls 2d6 and assigns one die to Survival and the other to Sanity. Each die is read separately: 5–6 avoids the consequence, 3–4 causes a lesser consequence and transfers one Blood to the GM, and 1–2 causes a severe consequence and transfers two Blood. Aiding adds a third die and keeps the best two, but every participant suffers the final results.
Dice	d100	2d6
Complexity	Medium	Very Low
Accessibility	High	Very High
Runnability	Very High	High
License	Chaosium Fan Material Policy	CC BY-SA 4.0
Cost	$$	Free
Publisher	Chaosium	Precision Chaos Machine
Year	2014	2021
Best For	Investigation-driven horror where combat is deadly and sanity is fragile. Great for one-shots.	Groups seeking a semi-competitive science-fiction horror one-shot where player elimination becomes active antagonist play.
Highlights	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.	Assigning one die to Survival and one to Sanity makes each opposed roll threaten body and mind independently. A defeated Responder becomes a Speaker who spends Blood on manifestations, keeping eliminated players active as antagonists. Four Acts raise the Speakers' manifestation limits and Blood supply, producing a complete escalation arc from briefing to escape.
Considerations	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.	The rules support one hostile-derelict scenario and contain no advancement or campaign procedure. Minor harm, serious harm, cracking under pressure, and meltdowns have no additional mechanical definitions, leaving their consequences to the table. The semi-competitive structure turns defeated characters into antagonists, changing play from cooperative survival to active opposition.