ESSER
Version 2.0Best For
Groups seeking a two-hour, genre-flexible one-shot where the same d20 engine handles action and conversation.
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.
One d20 roll and four result tiers cover most actions. Opposed margins and Interface tiers add a few choices without separate resolution engines.
- Free to tryFull core rulesLegally free as an SRD, PDF, or official web rules
- Get it nowAvailable nowFree to download or read online
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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.
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.
No verified third-party publishing route found · Reviewed 2026-09-25 · Summary only, not legal advice. Check current terms before publishing. Rules license Proprietary A bounded review of the complete official web rules found no stated third-party publishing route or explicit prohibition.
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