Worlds Without Number
1st EditionBest For
Groups who want an open fantasy sandbox where their own goals drive play. Faction turns and campaign-building tools keep the world moving between sessions.
Core Mechanic
Skill checks roll 2d6 plus the relevant skill level and attribute modifier against a difficulty. Attacks roll d20 plus base attack bonus, combat skill, and attribute modifier against the target's Armor Class. A missed melee attack can still inflict Shock damage when the target's AC is low enough.
The core is quick to teach: 2d6 plus skill for tasks and d20 against AC for combat. Depth comes from character building, where backgrounds, classes, and foci combine with magic traditions and spell choices. The GM-facing faction and campaign tools add a separate layer of study.
- Free to tryFull core rulesLegally free as an SRD, PDF, or official web rules
- Get it nowAvailable nowFree to download or read online
- ✓IndexFind any rule by page number
- ✓GM guidanceA chapter on how to run the game
- ✓Examples of playRules shown in action at the table
- ✓Quick referenceCheat sheet or summary tables
- ✓Cross-referencesRules point to each other by page
5 of 5 book tools found in the core book
Highlights
The campaign chapter turns worldbuilding into procedures, with tags and tables that keep sandbox preparation to one session ahead. Faction turns let rival powers act between sessions, so the setting changes even when the players are elsewhere. Shock damage keeps melee misses meaningful and makes armor and shields matter in close combat.
Considerations
Combat resolution is deliberately simple, with positioning and Shock carrying most of the tactical weight. The rules assume a sandbox campaign and offer little structure for pre-planned story arcs. Social conflict is handled by skill checks and GM judgment rather than a dedicated subsystem.
Third-Party Publishing
Rules license CC0 1.0 Universal (SRD 1.0); proprietary core books
Mechanics and trivially derived material in the 94-page SRD, including rules text, weapon damage dice, and spell and ability names. Excludes the Latter Earth setting, its nations, individual NPCs, GM tool text, and other creative IP. Compatible works must use their own settings and must not claim to be official or use confusing trade dress.
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