ESSER vs Mothership
Compare ESSER and Mothership side by side. See differences in complexity, dice, genre, and more.
| ESSER | Mothership | |
|---|---|---|
| Genre | Universal | Sci-Fi, Horror |
| Tags | Rules-Light, Theater of the Mind, One-Shot Friendly, Short Sessions, Fast-Paced, Low-Prep, Freeform Magic, Cinematic, Classless, Roll to Cast | Rules-Light, Deadly, One-Shot Friendly, Survival, Atmospheric, Low-Prep, Cinematic, Fast-Paced |
| Core Mechanic | Roll d20 + skill bonus + attribute bonus. A result of 1–9 fails with a complication, 10–14 succeeds at a cost, 15–19 fully succeeds, and 20+ succeeds with an epic effect. | Roll d100 under stat/skill. Stress and panic mechanics escalate tension. |
| Dice | d20 | d100 |
| Complexity | Very Low | Low |
| Availability | Free core rules | Free quickstart |
| Runnability | Book tools not listed | 4 of 5 book tools |
| License | Proprietary | 3rd Party License |
| Third-Party Publishing | No verified route found | Not yet researched |
| Summary only, not legal advice. Check current terms before publishing. | ||
| Publisher | Espen Erlandsen | Tuesday Knight Games |
| Year | 2026 | 2022 |
| Languages | English | English |
| Best For | Groups seeking a two-hour, genre-flexible one-shot where the same d20 engine handles action and conversation. | Terrifying sci-fi horror one-shots and short campaigns. Panic table creates unforgettable moments. |
| Highlights | The same d20 roll handles standard checks and direct contests, making transitions between scene types quick. Interface scales open-ended supernatural or technical effects by skill tier, letting one procedure cover magic and hacking. NPCs need a core bonus, Strikes, and an optional trait, so a GM can prepare threats with few statistics. | Rules-light, well-regarded module library, panic system creates mechanical tension |
| Considerations | No default setting is provided, so groups must supply a world for their adventure. Gear grants fictional permission rather than numeric bonuses, limiting equipment-based builds. Strikes reset after each adventure, so the track does not preserve mechanical attrition between adventures. | Panic table can cascade and end sessions abruptly, limited long-campaign support in core rules, stress mechanics can feel repetitive over extended play |