Welcome to OpenRPG

A percentile-based tabletop RPG system designed to bring players together around shared stories. Whether you're new to TTRPGs or a veteran GM, OpenRPG scales to your table with three distinct rule tiers.

Always free. Character creation, campaign management, and all core rules remain accessible to everyone. Premium features support development but never lock away the essentials.

Core Mechanics

• Percentile System: All rolls use 2d10 (1-100) for consistent, intuitive probability across all mechanics.
• 21 Attributes: Physical, Mental, and Sense categories provide nuanced character definition beyond simple ability scores.
• Scalable Difficulty: 7-tier system from Routine to Improbable. Your character sheet auto-calculates target numbers based on attributes and skills.
• Digital Character Sheet: Everything you need in one place, with auto-calculated difficulty tiers and GM sharing controls.

Character Creation

Start at level 1 with 50 points in each of 21 attributes, plus 200 bonus points to distribute. Choose your world (Openheim or Generic), ethnicity, profession, and religion. Define physical traits and craft your background story.

Growth happens through attributes, skills, professions, and imbuements—no two adventurers are alike.

Skills & Imbuements

Skills represent training: lockpicking, climbing, combat techniques, and more. Anyone can attempt anything, but success depends on attributes, invested skill points, and difficulty tier.

Imbuements are magical powers linked through rare artifacts. These define your supernatural capabilities and tactical options in Advanced Rules.

Combat & Risk

Combat is brief, intense, and deadly. OpenRPG currently uses sheet-generated difficulty targets as its canonical resolution model: choose the relevant combat skill, choose the difficulty tier, then resolve against the target number shown on the character sheet. In Advanced Rules, weapons deal size-scaled damage, armor provides layered protection with damage type modifiers, and positioning is tactical.

Consequences matter. Physical injuries, mental trauma, social repercussions, and supernatural curses reshape your character's story in Expert and Advanced play.

The current app supports combat action catalogues and target-number reference, but many live combat outcomes are still GM adjudicated rather than fully engine-enforced.

The World of Openheim

A dark low-fantasy setting where ethnicities clash, religions shape destiny, and ancient burgs hold secrets. Explore an interactive map with thousands of locations, or create Generic characters for your own worlds.