Old-School Essentials
Classic FantasyBest For
Groups who want treasure-driven dungeon expeditions and open wilderness campaigns with fragile starting characters.
Core Mechanic
Attacks roll d20 against an attack matrix or an optional ascending Armour Class target. Saving throws meet a category target on d20. Ability checks roll at or below an ability score on d20.
Attacks use a d20 with either an attack matrix or ascending Armour Class. Exploration procedures connect elapsed time to dwindling supplies and encounter risks. Most characters advance through fixed class tables rather than extensive build choices.
- 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
Treasure recovered from adventures provides most experience points, rewarding successful exploration over fighting alone. Reaction and optional morale rolls let encounters lead to negotiation or flight instead of automatic combat. Stronghold construction and taxation let accumulated wealth support a growing domain.
Considerations
Characters die at zero hit points, and failed poison saves are usually fatal. Demihuman characters combine ancestry with class and have lower level limits than human classes. Declared spells are lost if the caster is hit or fails a saving throw before acting.
Third-Party Publishing
Rules license OGL 1.0a
Declared Open Game Content in pre-2026 Classic Fantasy books; excludes the Introduction, artwork, logos, presentation, and protected names. Compatibility branding requires a separate license.
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