A generic RPG system based on ability scores

Posted by on January 8, 2014

This is a simple RPG system based on the classic D&D ability scores.

The Basics

To resolve a difficult action, roll 2d6 and add the relevant ability score modifier.

Roll Result
2 or less Disastrous failure
3-5 Regular failure
6-8 Failure with a benefit
9-11 Regular success
12 or more Spectacular success

To determine an initial ability score, roll 3d6.

Ability score modifiers:

Score Modifier
2-3 -4
4-5 -3
6-7 -2
8-9 -1
10-11 0
12-13 +1
14-15 +2
16-17 +3
18-19 +4

Attacks normally deal 1d6 damage and lower the appropriate Health score. Health is restored at a rate of 1d3 points per day.

The GM can add +1 or -1 depending on the situation.

Each hero also has one catchphrase, which can be used once per session for +2 on a roll.

At the end of a story, the GM may reward each player with up to 2 points to add to ability scores.

Heroic Fantasy

Ability scores:

  • Strength
  • Dexterity
  • Constitution
  • Intelligence
  • Wisdom
  • Charisma
  • Health

Superheroes

Ability scores:

  • Strength
  • Stamina
  • Agility
  • Fighting
  • Intelligence
  • Awareness
  • Presence
  • Physical Health
  • Mental Health

Horror

Ability scores:

  • Strength
  • Awareness
  • Lore
  • Physical Constitution
  • Mental Constitution
  • Physical Health
  • Mental Health

Science Fiction

Ability scores:

  • Body (Strength)
  • Body (Agility)
  • Knowledge (Technical)
  • Knowledge (Galaxy)
  • Awareness
  • Charisma
  • Physical Health
  • Mental Health

Optional Rules

Magic

Add another ability score: Magic.

To cast a spell, you must first spend 2 points for a trivial spell (brief light, temporarily vanish an object, throw your voice), 4 points for a basic spell (equivalent to what another person could do with skill and equipment, like a fireball that’s equivalent to a flaming arrow), or 6 points for a major spell (crumbling a wall).

After spending, re-calculate your Magic modifier, then roll 2d6 and add your new Magic modifier. Use the normal resolution rules.

Magic points recharge 1d3 points per day.

Healers

Add a Healing ability score. Once per day, you can roll and add your Healing modifier. You heal one-fourth the roll’s value in Health (rounded down, minimum 1) on an ally or yourself (no success or failure).

Credits

This game was written by Brent P. Newhall, inspired by core rules written by Brian Takle.

Download a clean PDF of this game at DriveThruRPG.